DOCUMENTED CHROMOSOME NUMBERS 1993:2. ADDITIONAL CHROMOSOME COUNTS IN THE MALVACEAE

9 Pages·1993·4.9 MB·English

by  Paul A Fryxell

DOCUMENTED CHROMOSOME NUMBERS
1993:2.
CHROMOSOME
ADDITIONAL COUNTS
THE MALVACEAE
IN
PAUL FRYXELL
A.
U.S.D.A.
Agricultural Research
Service,
&
Department Crop
Soil Sciences
of
A&Al
Texas University
TX
77843-2474
College Station,
DAVID
STELLY
M.
New
Beasley Laboratory
&
Depart?nent of Soil Crop Sciences
A&M
Texas University
TX
77843-2474
College Station,
ABSTRACT
Chromosome numbers are reported for 29 species of Malvaceae in 3 genera, of which 8 are
1 1
new reports. The taxonomic impHcations of these data are discussed.
RESUMEN
Se reporta niimeros cromosomicos para 29 especics de malvaceas en generos, de cuales
las 3 las
1
18 son datos nuevos. La significacion taxonomica de estos datos esta considerado.
INTRODUCTION
Chromosome numbers have been useful in evaluating generic boundaries and
many
generic and tribal relationships in families, including the Malvaceae (Bates
The
1966, 1968, 1976; Bates and Blanchard 1970; Krapovickas 1957, 1969).
opportunity obtain counts and previous counts (Table permits
to nevv^ verify
1)
the extension and revision of previous interpretations of relationships within the
Malvaceae.
AND METHODS
MATERIALS
made grown
All counts were on samples taken from greenhouse-grown plants,
from seed samples taken from voucher specimens indicated in Table Voucher
1
.
specimens kept herbarium College
are in the senior author's in Station, Texcis;
may
additional duplicates of these collections also be found in other herbaria,
^is
noted the
in table.
95% minimum
buds were
Floral fixed in ethanol: glacial acetic acid, for a
3:
1
,
of 24 Prior to preparation of specimens, the buds were rinsed and allowed to
hr.
639-647.
SiDA 1993
15(4):
640 SiDA 1993
15(4):
New
Clirtjmosonu' tuinibcrs of sclecuxl species of Malvaceae. counrs are indicare<.l with an asterisk {*).
Tari.i-.
1 .
1 Origin Voucher
Species u
/270J,MnXU
Abiitihni M.F.. Jones 6 '^ Mexict). Nayarit Tellcz
Ihiyyiniiiiv
1
Torrey ex Gray
MFXU
hiihiMuum 14 Mexico. Veracruz rfW>w.S56\S,
Ahuttliin (Torr. l^ Cjray)
Ahutdou 14* Mexico.
nhicViUigl)}} I'ryx. Jalisco
14* Fo.u'//j.S3^,CANB
Ahi^lilofi otoaiyjy/nN Miiell. Australia
F.
Ahi/lilon /h/risl)!/ S. Watson 14* U.S.A. Arizona Vdri Dvnndey d dl.
ARl/
91-808,
NY
Hocht. 14* Mexico. Veracruz Nee O'ldylor 28^^)0,
Ahi/lilon sphiii'vostiViinium
^Y
&
Mexico
AlloirisSiuli/hi Jlinh/ohlif (Schltdl.) I'ryx- 6 Jones Tyeidflt) 168,
I
AholLi dljiitilmdcs A. Gray 30 U.S.A. Arizona Vdf/ Dfvoidcy vl dl.
ARIZ
97-959,
*
Auikld dUu Fryx. 30 Mexico. Michoacan Fo'.\v//30/2,NY
flora
AnocLi [hilmatci Fryx. ^0 Mexico. Jalisco Koc-b&Fryxe// 89193.
CHAPA
24*
Veneztiela rryxi'//&B//ydm//4393.T'
32*
Bjtaiuulvii vtohued (Rose) Fryx, U.S.A. Texas Wurdiiik
s.n.
NY
nUoiucdid 21)* Mexico. San Luis Potosf Jom's 147,
Fr)^x.
C'n:)tfne\:^fis'h}
CTES
Cienffii'gosia almtfolsj Fryx. 21) Art;ennna Schidz
s. }}. ,
UCR
Uirhiimphis uiexwcina Fryx. 30* Mexico. Jalisco LotUidl. 4042,
NY
Fryxi'llid (Curr.) Dates 16 Mexico. Coaluula Frj:vr//5006,
l)yy^ifhiea
uilypljylhis Cav. 80 Hawaii. Kauai without coll.. Seed acc. no
llihisi/L\
WaimeaB.G.
74s72.\
UCR
Hihiki/s cttYDun Fryx, 22^'. Mexico. Jalisco Lonetdl. 4083,
32* Hardy /"
Jlihisa/s grd)ul!iliai Baillon Ma(.la^^ascar s.n., N^i
CANB
Biirm. 24 Australia Frj.u7/4530,
]lihtsctis pdiidiiyijormis hi.
^G
AN
36* B
Mnell. Australia Frj.w// 443
llibisais pcNldphylli/s
F.
30* Mexico. Sonora Sdmlcr^4620,\K:\\
HorsJon//d cxd/i/fd I'ryx.
& 56* Kodj&
PdJ'onid Fryx. Kocli Mexico. Jalisco Fry xd/ 89198,
i'costdlii
CHAPA
rryxci/4939,NY
Vbyuiuud Huibclldta (Cav.) Kearn. 34 Mexico. Tamatilpas
Cm/r/W CTES
2079,
S'ldd drgeuliud var. tucnvhimnsis Hassler 11 Ari^entina. Salta
ex Rodrii^o
BRIT
Sidd FnL;elm, Gray 28 U.S.A. Texas frjA.// 4964,
lifidheiffiLri
«S:
M* GANB
Sidd ndjlaidc var, nmt'ud (Benth.) Fr)'x. Australia Fo.u//4428,
SphdiTidaui A, Gray 30 U.S.A. California Pifzcr /97,U(:R
Lii)d)'igNd
TEX
20*
Sphairalaa Fryx. Mexico. Goahuila Fryxd! 4997,
nflcxd et al, dl.
L't
soak tap wattr or distilled water for several hours. Anthers were dissected from
ill
the buds, placed in acetocarniinc stain, then cut and macerated to release
microsporocytes. Preparations containing microsporocytes at stages suitable for
chromosome counting were covered with covershp and repeatedly heated and
a
The
cooled until chromatin was satisfictorily stained. cells were then sc|uashed,
and were with wax. Counts were made under immersion
the coverslips sealed
oil
brightfield occasionally, phase-contrast optics on an Olympus Vanox micro-
or,
Kodak
specimens were photographed using Technical Pan
Sufficiently
scoj^e. flat
2415.
film
and
FRYXELL Chromosome
Stelly, counts in Malvaceae 641
AND
RESULTS DISCUSSION
The
summarized
results of these studies are in Table
1.
Chromosome
Abutilon.
counts genus
for six species are reported in the
A
huhmnum
Abiitilon (Figs. previous count for A. (Bates 1976)
1, 2). verified,
is
new
and reports are presented for the remaining five species Four of these five have
.
a chromosome number oiln = l4, which conforms to the base number of x = 7
for the majority of species in the genus, Abutilon harrancae, on the other hand, has
In = 16. This species represents Abutilon sect. Anasida (cf Fryxell 1988, p. 25).
Those
species that have been or can be placed in this section, and which have been
=16,
counted, also have chromosome numbers of 2n including Abutilon
coenocyticspomd showing
Fro. MicrosporocyteofA^//r/7(??7 hctrranccw. stage, four nuclei, each
1
,
with eight chromosomes 18
(bar )am).
:=
Fig. 2. Microsporocyte oi Abinilou parhljii: coenocytic sporad stage (at early cytokinesis),
showing four nuclei, each with seven chromosomes (bar = 20
)Llm).
Fig. 3. Microsporocyte oiHiljiscus dtrnms\ coenocytic dyad stage, each of the two poles having
chromosomes 20
(bar ^
1 1 jLlm).
Fig. 4. Microsporocyte oi Hibiscus grandidien: diplotene stage with 6 bivalents, one closely
1
associated with the darkly staining nucleohis (bar = 15 )im).
K
(
642 SiDA 1993
15(-i):
anckrssouuiuiini Garcke, A, dliptianu Schkdl., A. thurhcri A. Gray, A. miibeUcJtinn
(L.) Sweet, A. virgatnrvi (Cav.) Sweer and VseiicLtbiittlon adlimorphimi (Hochr.) R.E.
,
group
Fries (Bares 1966, 1976; Fernandez 1974; Krapovickas 1957). This of
supported by
species clearly distinguished cytok)gicalIy, a distinction that
is
is
morphok)gical characters, and the c]uesrion must be raised whether sect. Anasida
name
merits elevation to generic rank. If so, the VseNduhatiUm available,
is
altliough several new combinations would be required, and the generic bound-
The
aries originally proposed by Fries (1908) would have to be revised.
who
typification of Pseiidcd)i{td(m was discussed by Fryxell (1988, 75),
p.
concluded that the type species PieadahNtUon scahriim (Presl) R.E. Fries [=
is
M.E.
Abiitdini hcinancae Jones].
chromosome number
Another by
grou]:) of Abi/tilon species characterized a
is
= wW/tr-yJvVwc/Gurke&Scluimann,
of l6(e.g. A. inaeq/nIcncr/n}iSi.-Y[i\.,A.
2//
&
A, Griseb., A. piciaui (Hooker Arnott) Walp., A. purpusii Standley, A.
niveii)}!
may
Mic]uel, and A, Dicks, ex Lindl.), but these be assigned to
regudlii struit/ini
and
Abiitdo)! sect. Phiviovidatae Fryx. are outside of the present discussion.
A
The rms
Allowissadula. count of = 6 Hon con the
2/; for 'issadidajlordyufid^t
fi
1
chromosome number
previously reported for this species (Bates 1978, as A.
Of
mkroudyy. (Rose ex R.E. Fries) Bates). the nine species of this genus, five are
known cytologically, of which have the same chromosome number.
all
Anoda. The chromosome
three species oi Aiiodc^ reported here have the
all
number 2)1 = 30, which conforms to the known b^ise number for tlie genus, x -
The
15 (Bates 1987). values for A. abiitdoides (Fig. 5) and A. palmata are
confirmations of previously reported counts (Bates 1987), and the report for A.
The polymorphic and
new. latter species for corolla color, the
albiflora is is
available seed saniple was segregating for white- and lavender- flowered plants.
Both flower color forms have the same chromosome number.
The new Only
Batesimalva. count of = 32
for B. violacea (Figs. 10).
2;/ is 9,
chromosome
one previous count in Bcitesbucdva has been reported, also 2n - 32
^ov B.jv/1chella Y'cyy.. (Bates and Blanchard 1970,asG'<:/j'<;/aff violcicea). Thisspecies
both morphologically and phytogeographically.
very similar to B, violacea,
is
The count of 2/; = 24 for B. killipii also new (Fig. 3) and presents a number
is 1
m
that seldom encountered the Malvaceae. In the tribe Malveae, counts of
2;/
is
Gaya
= 12 and 24 have been reported principally in the genera (Krajiovick;.is
1957; Fernandez 1974, 1981; Bates 1976) and Malvastrum (Hill 1982), as well
as from a few species ofCr/sfar/a (Krapovickas 1957) and Lecanophora (Krapov-
cannot be with any of these genera,
ickas 1950). Bates'unalva killipii allied
1
them
liffering substantially from of in morphological terms.
c all
At the same time, the chromosome count of = 24 Batesnualva
2// for killipii
differs from the counts of 2// ^ 32 reported for other species o{ Batcsivudi'a (see
previous paragraph), and the two counts are not readily reconciled. Therefore, the
The
generic placement of B. brought into question. species was
killipii
is
and
Fryxell Chromosome
Stelly, counts in Malvaceae 643
^^,^^
.Mkrosporocy
Fig. 5 te o^Auocfa a/wt//ou/cs\ late c!iplocenestage(nucleolLis barely visible), with
15 bivalents ar unusual semi-contracted state (bar = 9
|-lni).
Fig. 6. Microsporocyce of D/rhawp/j/s mexkana: diplotene stage, sliowing 15 bivalents, three
attached or partially superimposed on the nucleolus (bar = 6 jJm).
I
Fig. 7. Microsporocyte o^Fyyxdlui pygviaed: diplotene stage, showing R bivalents (bar = 16
Llm).
efl<
- 12 Urn).
originally placed in Batesimalva because shared features of mericarp morphol-
it
known
ogy with
previously species of the genus, although differed in (and
it floral
other) characters and inphytogeography. In view of the cytological difference here
reported, the generic boundaries oi Batesimalva will need to be reconsidered,
new
including the possibility of a generic placement for B. kiUipn.
C
Cienfuegosia. The chromosome counts of = 20 for intermedia a new
2;;
is
report, and the same count for C. confirms the report of Palacios and
idviifolta
Tiranti(1966). These counts agree with the numbers reported other American
for
known
species of this genus that are cytologically (Wilson and Fryxell, 1970).
Dirhamphis. The chromosome number
of 2// ^ 30 (Fig. 6) reported here for
644 SiDAl5(4): 1993
^^1
y
1
^^^^^H
»
• •
^^^^^B
^^^^^1
^^^^^1
^^^^^1
^^^^^1
^
^*
^
1 '
1
\
1
•*
^^^^^H
% «
%
» \
•
1
m
1
p P>
r-^ ^
9
\\ |io
^
^^f^
^^-' ^^
%
\x ^.^ V
K^
*
(^ V Xl '-
>
^i
^;^^
W^
ti
-K
\^^
^^
'^^'T .»*
v..ri
^^J
^-
f
\^
="^ -*:-.
^J
-^
^
X
*s t^ - Ki^
*
-W ''<*
^»
1 >
^
1
^ 4^
* r 4
«
^1 ^ ^
*%
f
%
^ ^.
»
*
"^t^- A
> % ^
-1
%
J*
f
«
4t
ft
*
^_
-^
#«.
.-f
.
« > f '^
: ^
*-
'^
*
• ^
^V
^ -i
I
^iv «
«
''^
13
f >* *-
€.. *
's.
r'-: i
** ts % ^-
m % %
*
Figs. 9 '^nd 10. Microsporocyces o[ Safes////ah'c/ vioLicecr. early metaphase I, wich 16 bivalcnts
-
(bar
18|-ln-i).
Figs. and 2. Microsporocytes of SiiLi rohleuaevAr. niutica: iNchipbcisel, with seven bivalcnts
1 1
1
(four "nxls" and tlTree"rings")vs. six bivalents (one rod) plus two univalents (off metaphaseplate),
and
respectively (bars = 13 respectively).
1 \\\ix\ |^^*ii,
Two
microsporocytes of meraphase each with 2 bivalents (bar
Fig. 13. Bi/tes/f?k//ra killipii:
I,
t
= pm).
8.9
and
FRYXELL Chromosome
STELLY, counts in Malvaceae 645
D, mexkana new The
a report. otlier species of the genus, D, halansae Krapov.,
is
has been reported as 2;^= l4 (Fernandez 1981). Fryxell (1988, suggested that
6)
p.
group
a of four genera {Batesimalva, Horsfordia, Briqiietia, and Dirhaviphis)
constitute a generic alhance, based largely on a commonality in fruit structurcj
may
but this view need to be revised on the basis of chromosome numbers
reported here, as discussed further in the following paragraph. Further, because
of chromosome numbers, two Dirhamphh may
disparate the species di not be
congeneric.
The
Fryxellia. cotmt of 2/2 = 1 6 for /^ pygmaea (Fig. 7) was previously reported
(Fryxell and Valdes 1991) and the preparations was suggested
cell illustrated.
It
may
that a phylogenetic relationship exist between Ffjxellia and Bateshnalva,
common
which chromosome
possibly share a base number. This finding provides
a hypothesis for evaluation using other classes of data. Moreover, the other genera
On
noted above need be brought
also to into the discussion. the basis of
chromosome numbers now available^ this group may need to be divided mto at
two
groups, one with x - {Pirhamphh mexkana and and one
least 15 Horsfordia)
with X = 16 (Batesmaha) or x = 8 {Fryxellia). Briquetia (x = 7) may not relate to
may
group but The
either be better placed in the Ahutilon alliemce. position of
Dtrhamphis mexkana and we
that oi Batesimalva killipii rec]uire further study, but
now
have framework
a for discussion.
Chromosome
Hibiscus.
counts for five species are reported here, three of
which
are new. Previous reports for Hibiscus pa mhiriforviis (Skovsted 1941;
Dasgupta and Bhatt 1976, 1982; Bhatt and Dasgupta 1976; Krishnappa and
Munirajappa 1980) have all given the same result as found here, 2yi = 24, even
though The
this species highly variable morphologically. count o{2n = 80 for
is
H. calyphyllus conforms to previous counts reported by Skovsted 94 Niimoto
(1
),
1
&
(1966), Kachecheba (1972) and Krishnappa Munirajappa (1980), but differs
from a report of 2a; - 40 by Bates 966); the species evidently exists at two ploidy
( 1
levels.
^22
The
count of 2;; for H. citrinus (Fig. 3) conforms to similar counts reported
New
World
for other species oiHibisc/Ls sect. Bombicella, H, biseptus S. Wats., H.
denudatus Benth.^ H. martianus Zucc, and H, (Skovsted
phoeniceus 1935,
]z.qq^.
1941; Bates 1976), indicating that the American members of this section are
cytologically quite uniform.
Chromosome numbers
which
for Hibiscus sect. Bombkella, the section to H.
grandtdieri belongs, were reviewed by Fryxell (1980). The count here reported
(Fig. 4) for H. grandidieri {2n = 32) conforms to counts for two other African
Brown
species of this section {H. mutatus N.E. and W.fen^ugineus Cav.) but
differs
from the tetraploid count 2n = 64 for//. nncranthus'L. f and the count of = 22
2;/
The
H. Thunberg. count same which
for pusilliis latter the as that cliaracterizes
is
American known
the five species of section Bombicella that are cytologically
(Fryxell 1980; see previous paragraph).
SiDA 1993
646 15(1):
^phylL
However,
similarspecies H. rv7cw/vGarcke(Dasguptaand Bhatt 976, 9S2). the
1
1
chromosome number
base of x = 8 also characteristic o^Hihiscus sect. Finraria,
is
1
Menzel&
Wilson
tph)
much
Thus clear that remains to be learned about the generic subdivision
it is
polymorphism.
genus of considerable cytological
o^HihiscNS, a
(W:
(W:
The
30 (Bates 966, 976), reported here for H. exalata. genus appears to be
is
1 iis
1
uniform, and shares a base chromosome number of x ^ 5 with Dirhamphh
it 1
discussed previously.
mex'icana, as
Pavonia. Chromosome counts more 25 species o^Vavoma have been
for tlian
and have been various ploidy
reported in the literature (Fryxell, in prep.), all at
based on x = The new count of = 56 conforms to this
levels 7. for P. ecostata 2;/
pattern and indicates the species octoploid. This the only count yet reported
is is
Pciimuasv\hgi^n.Malmioe,Pcnwncrc\ndHih'Lscusptt^^
^or
Both are large genera with more than 200 species, but Pavoma cytologically
is
uniform with a single base number, whereas Hibiscus highly polymorphic witli
is
wide range of base numbers.
a
Phymosia. The report of 2// = 34 for Phymosia ionhellata confirms previous
Webber
1976;Skovsted 1936) and previous
reports for this species (Bates 1935;
and Blanchard
counts for other species in the genus, P. rosea (DC.) Kearn. (Bates
and P Hamilton (Webber
1970) 1936).
ahiitilouks (L.)
Two new Both
Sida. of the three counts reported here iox Sulci are reports. Sida
argent luu var. tiiaimarmisis and Suki rohlemie var. vmtica have 2n-^ l4 (Figs. 11, 12),
common The
the most count reported tor species oiSicLi. tetraploid count of 2;/
= 28 for SicLi Ihnlheimeri confirms a previous count (Krapovickas 1969)-
A
chromosome number x
Sphaeralcea. b^ise of = 5 characterizes this genus,
and countsof2// = 10, 20, and 30 have been reported for various species, including
amhigiici, reported here as having 2;/ ^ 30. The count of 2;/ = 20 for S. rejkxa
S.
new
a report (Fig.
8).
is
ACKNOWLEDGMl'NTS
We
Wiens Kenneth
are grateful to for seed samples o{ Abiitilou pcrrishii^ to
J.F.
Waimea
Wurdack and Botanic Garden,
for seeds oiBatesinudva violacea, to the
J.
Haleiwa, Hawaii for seeds diHihisais grandidieri and of W. adyphylhis (received as
The ofJuan Dfaz-Colon in making chromosome preparations for
//. rockji). skill
microscopic examination also greatly appreciated.
is
and
Fryxell Chromosome
Stelly, coLints in Malvaceae 647
REFERENCES
D.M. Chromosome numbers
Bates, 1966. in theMalvales. Genres Herb. 10:1-116.
I.
D.M.
Baths, 1968. Generic relationships the Malvaceae, Malveae, Gences Herb. 10:117-
in tribe
135-
D.M. Chromosome
Bates, 1976. numbers in the Malvales. Miscellaneous counts from the
III.
Byttneriaceae and Malvaceae. Gentes Herb. 143-1
50.
1 1
:
D.M. new
Bates, 1978. Alloivissadida^ a genus of North American Malvaceae. Gentes Herb.
11:329-354.
D.M. Chromosome
Bates, 1987. numbers and evolution Anoda and
in Periptera (Malvaceae).
Ahso
11:523-531.
Bates, D.M. and Blancuard, 1970. Chromosome numbers theMalvales New
O.J. Jr. in or
II.
otherwise noteworthy counts relevant to classification in the Malvaceae, tribe Malveae. Amer.
57:927-934.
Bot.
J.
Bi R,P. and A. Dasgupta. 1976. Cytotaxonomy of Malvaceae Chromosome number and
lA'rr,
I.
karyotype analysis of Hddsa/s, Azauzd, and Urena. Cytologia 41:207-217.
lOPB
Dasgupta, A. and R.P. Bimtt. 1976. chromosome number reports. Taxon 25:494.
Dasgupta, A. and R.P. Bhatt. 982. Cytotaxonomy ofMalvaceae Meiotic
III. studies oiHihisais,
1
Akhnoschus, Azanza, Thespesia, MaLahra, and Pavonia. Cytologia 47:109-1
lJre)ia, 16.
Fhrmaxdez, a. 1974. Recuentos cromosomicos en Malvaceas. Bol. Soc. Argent. Bot. 15:403-
410,
Fernan[:)EZ, a. 1981. Recuentos cromosomicos en Malvales. Bonplandia 5:63-71.
Fries, R.E. 1908. Entwurf einer Monographic der Gattungen WissaduLt und
PseudcdMitihm,
Kongl. Svenska Vetenskapsakad. Handl. 43(4):1-1 14 + 10
plates.
A
Fryxell, PA. 980 revision of the American species of section Bojuhicella (Malvaceae).
1 ///7;/jr//j
Techn. Bull. U.S. Dept. Agric. 1624 1-53).
(pp.
PA.
Fryxell, 1988. Malvaceae of Mexico. Sysr. Boc. Monogr. 25:1-522.
PA.
Fryxell, and Valdes R. 1991. Observations on Pryxdlut pygmaea (Malvaceae). Sida
J.
A
Hill, S.R. 982. monogra]-)h of the genus Ahdvc/stn/in A. Gray (Malvaceae: Malveae). Rhodora
1
159-264,317^09.
84:1-83,
Kaulecheba, The cytotaxonomy some Kew 27:425^33
J.L. 972. of species oi H/i^/sa/s. Bull.
1
+ 2 plates.
Krapovickas, A. 1950. Revision del genero Lcanfophora (Malvaceae). Darwiniana 9:248-279.
Krapovickas, A. 1957. Niimeros cromosomicos de Malvaceas americanas de tribu Malveae.
la
Rev. Agronom. Noroeste Argent. 2:245-260.
Krapovickas, A. 1969. Notas citotaxonomicas sobre Malvaceas. Bonplandia 3:9-24.
Krisiinappa, D.G. and Munirajappa 1980. lOPB chromosome number Taxon
reports. 29:536.
Menzel, M.Y. and F.D. Wilson. 1969. Genetic relationships in Hibiscus Pinraria. Bnttonia
sect.
21:91-125.
Chromosome
NiiMOTO, numbers some
D.FF. 1966. of Uibiscus species and other Malvaceae.
Baileya 14:29-34.
Palacios, R.A. and l.N. Tirantl 1966. Niimero cromosomico de especies argentinas de
Cienfuegosici Cav. (Malvaceas). Inst. Nacional de Tecnologia Agropecuaria, Bol. No.
4(). (9 pp.
6
+
figs.)
Chromosome
Skovsted, a. 1935. numbers in the Malvaceae. Genet. 31 :263-296.
I.J.
Chromosome
Skovsted, a. 1941. numbers the Malvaceae. Compt. Rend.
in Trav. Lab,
II.
Carlsberg, sen Physiol. 23:195-242.
Werrer, Chromosomes
J.M. 1936. in SphderaliCij and related genera. Cytologia 7:313-323.
Wii^soN, F.D. and PA. Fkyxlll. 1970. Meiotic chromosome numbers and
oi'denf/zegosia species
hybrids and Hampea species. Bull. Torrey Bot. Club 97:367-376.