3 0 INTBODDCTOBY ESSAR.
I n a few species, like C. irhpermua and C. mmillensis there are t h r e e f a i r ly
e q u a l l y developed seeds in each f r u i t C. Burckianvs also has as a rule t h r e e seeds,
b u t occasioually only one developes fully a n d only a conspicuous r u d i m e n t of each
of the two others remains. When t h e r e are t h r e e seeds t h e y arc convex e x t e r n a l ly
a n d h a r e two flat f a c e t s which meet at a central obtuse angle. In C. Huegelianv»
a n d C. digiiaius there are occasionally two seeds and then they are plano-convex.
E x c l u d i n g these few exceptions, the fruit of Galanms as a rule contains only
c u e seed, and t h e r e m a i n s of the other two are absorbed ; this seed is commonly
g l o b u l a r or ovoid or even s l i g h t l y flattened and s u b l e n t i c u l a r ; e x c e p t i o n a l l y it is v e ry
i r r e g u l a r l y s h a p e d and a n g u l a r as in C. faspalanthus, C. gonospcrmui and G, ornatue.
T h e seed of Calamus is always erect in the f r u i t , and even when it is flattened
or lenticular its l o n g e r axis is the vertical one.
I n most seeds of Calami it is possible to d i s t i n g u i s h a dorsal a n d a v e n t r a l side,
t h e dorsal being usually convex, while the ventral has g e n e r a l l y iu t h e centre a
c i r c u l a r or elliptic d e p r e s s i o n (PLATE 230, figs. IC, 18, and 19; t e r m e d t h e " c h a l a z al
f o v e a , " w h i c h in the seeds of several species is r e p r e s e n t e d by a l o n g i t u d i n al
f u r r o w or even by a small i n c o n s p i c u o u s rib. The exact s i t u a t i o n of the chalazal
f o v e a , though sometimea only f a i n t l y indicated, is always d i s t i n g u i s h a b l e even
w h e n the seed is globular.
T h e surface of the seed is l a r e l y , as in C. paspalanthiia, quite smooth ; most
f r e q u e n t l y i t is m a r k e d by small impressions, pits or alveoli, a n d f u r r o w s with coires
p e n d i n g ridges, wrinkles, small t u b e r c l e s , and similar i r r e g u l a r i t i e s ; t h e s e r i d g e s and
f u r r o w s o f t e n r a d i a t e f r o m t h e chalazal fovea.
T h e proper i n t e g u m e n t of the seed, as has a l r e a d y been noted, c o n t a i n s at
t i m e s t a n n i c s u b s t a n c e s , and this is u s u a l l y t h e case when the surface of the seed
i s i r r e g u l a r and especially when it ia p i t t e d and t h e i n t e g u m e n t p e n e t r a t e s more or
l e s s i n t o the substance of the albumen. When the i n t r u s i o n s of the i n t e g u m e n t are
s u p e r f i c i a l , the albumen cannot be considered r u m i n a t e d , but in not a f e w cases
t h e d e p r e s s i o n s on t h e s u r f a c e of the seed are very deep, and s o m e t i m e s these are
d e v e l o p e d into true narrow channels so t h a t the albumen is r e n d e r e d t y p i c a l ly
r u m i n a t e . This is a c o n d i t i o n t h a t obtains in t h e seeds of species of t h e allied genus
Daemonorops ; in this l a t t e r genus, however, a r e m i n a t e d seed is t h e rule, whereas in
Calamus it is the e x c e p t i o n ; in both cases the channels are filled with a brown
a s t r i n g e n t t a n n i c substance.
I n the i n t e g u m e n t of the seed of C. Flagellum, when dry, I have observed
n u m e r o u s obloîig or f u s i f o r m small bodies of a g a r n e t - r e d colour visible even to
t h e n a k e d eye, but of course much more obvious with the aid of a lens ; these
b o d i e s seem to be m u c i l a g i n o u s masses i n f i l t r a t e d w i t h t a n n i c acid, which fill corres
p o n d i n g l y s i g e n e t i c c a v i t i e s of the i n t e g u m e n t . The r u m i n a t i o n of the seeds of C.
• cilaris, C. exilis and allied species is of a very special n a t u r e . In these, the seed
i s d e e p l y and b o l d l y p l i c a t e and has a c e r e b r o i d a p p e a r a n c e ; t h e i n t e g u m e n t is very
t b i n , p e n e t r a t e s into the folds, m a n y of which r a d i a t e f r o m t h e chalazal fovea, and
18 f o r m e d of a few l a y e r s of p a r e n c h y m a t o u s cells filled with very small green
c o r p u s c l e s p a r t l y s o l u b l e in water, to which they impart t h e i r colour and a very
KXTRA-FLOIUL HECTABIES. 3 1
b i t t e r taste. Dr. V e t u r i a Bar t o i l e t ti, who has made a special study of this subs
t a n c e , * states t h a t it is p r o b a b l y a d e r i v a t e of t a n n i c ucid.
ID the genus Calamus the r u m i m i t i o n of the seed is nob of g r e a t t a x o n o m ic
v a l u e , because it h a p p e n s t h a t of two species which, f r o m m a n y p o i n t s of view, m ay
a p p e a r v e r y n e a r l y allied, one may have h o m o g e n e o u s , t h e other r u m i n a t e d a l b u m e n.
I t is not t h e r e f o r e possible to make use of the c h a r a c t e r of h o m o g e n e i t y or rumin
a t i o n of the a l b u m e n as a means of d i v i d i n g Calamus into t w o p r i n c i p a l sections.
L e a v i n g out of account its r u m i n a t i o n , the albumen of t h e seed of Calamus is
a l w a y s h o r n y or b o n y . In t h e d e s c r i p t i o n s of t h e albumen it is t e r m e d homogeneouB
not only when it is really so, but o f t e n also when the i n t r u s i o n s of the
i o t e g u m e n t are very s u p e r f i c i a l . The r u m i n a t i o n of the seed is very a p p a r e n t in
0, ereotus, C. Flagellum (and its a l l i e d species) C. Uuegelianus, C. Gamhlci, C. gracilis
C. jnclanacanthis, G. Diepenhorstii, C. macrosphaeriotiy etc.
T h e embryo of the seed of Calamus is most commonly situated at or n e a r its
b a s e (PLATE 230, iig. 13), but it is lateral and opposite to the chalazal fovea ia
C. exilis, C. ciliaris and other species of the g r o u p . It is also l a t e r a l in C. gracilis
a n d C. melanacanihus which have, besides, a r u m i n a t e d albumen, while in C. Kuaseanus
it is l a t e r a l a n d t h e a l b u m e n is h o m o g e n e o u s (PLATB 330, figs. 18, 19).
XIX-—Extra-floral nectaries.
So f a r aa I know n e c t a r i f l u o u s s u r f a c e s of any k i n d h a v e s e l d o m t b e e n observed
i n the flowers, and never h i t h e r t o in any of the other organs of Palms. It
a p p e a r s to me, however, t h a t c e r t a i n special s w e l l i n g s or callosities, which f r e q u e n t ly
e x i s t in c e r t a m d e f i n i t e p o s i t i o n s , in not a f e w species of Calamus, should possibly
b o c o n s i d e r e d e x t r a - f l o r a l n e c t a r i e s.
I have already a l l u d e d more than once, in passing, to t h e e x i s t e n c e of these
s u p p o s e d n e c t a r i e s , which are to be met w i t h : 1st, at the i n s e r t i o n of the leaflets
on the r a c l u s in t h e i r upper axil ; and, in the hollow f o r m e d by the folding
of the leaflets at t h e i r base, just at t h e i r i n s e r t i o n in t h e lower s u r f a c e ; 3rd, at
t h e i n s e r t i o n of the spadices and flagella; 4th, in the axil of every b r a a c h i n g of
t h e s p a d i x and its s u b d i v i s i o n s , s u c h as t h e spikelets and the i f i v o l u c r o p h o r a.
I have never had any o p p o r t u n i t y of s t u d y i n g these n e c t a r i f o r m surfaces,
as t h e y m a y be t e r m e d , in a f r e s h c o n d i t i o n ; in d r y specimens it is difficult to
i n v e s t i g a t e t h e i r true nature. These surfaces always have t h e a p p e a r a n c e of small
s w e l l i n g s of a l i g h t e r colour t h a n t h e a d j a c c n t tissue and are f o r m e d by two lips,
m o r e or less t u m e s c e n t , s e p a r a t e d by a c l e f t or rima, w h i c h m a y be supposed to be,
i n some casos, n e c t a r i f l u o u s.
Most Calami are p r o v i d e d w i t h t l i e s e s t r u c t u r e s , w h i c h are p a r t i c u l a r l y conspicuous
i n the axils ot the leaflets of C. pcrakensis and G. ramosissimus, and are e x t r e m e ly
d e v e l o p e d at the j u n c t i o n of the p a r t i a l inflorescences with the axis of t h e f e m a le
s p a d i x and in the axil at the i n s e r t i o n of the s p i k e l e t s in C. paspalanihus. As good
e x a m p l e s of the supposed n e c t a r i f o rm s t r u c t u r e s situated in the axils of tho
i n v o l u c r o p h o r a I m a y cite C. Gamblei, C. unifarius var. Pentong, C. adspersus, etc., and
• Bull. Soc. Bot. Ital. 1904, p. 309.
t Fide Delpino in NUOTO (Jiorn. Bot. It. n (1870), p. 61.