524
Palaeoruoiogie.
T h e r e w o u l d s e e m to b e little d o u b t that t h e s e s p o r a n g i u m like o r g a n s b e l o n g to Glossopteris Browniana, a l t h o u g h the evid e n c e is in p a r t indirect.
T h e s e sac-like b o d i e s h a v e n e v e r
b e e n o b s e r v e d e x c e p t in close relationship to the scale-leaves
of t h a t plant. F u r t h e r s o m e of the a s s o c i a t e d scale-fronds s h o w
w h a t possibly m a y b e i n t e r p r e t e d a s t h e s c a r s of a t t a c h m e n t of
t h e s e s p o r a n g i u m - l i k e b o d i e s , a n d also p o r t i o n s of t h e sac-like
b o d i e s t h e m s e l v e s , which h a v e the a p p e a r a n c e of b e i n g still in
c o n t i n u i t y . F i g u r e s a r e given of o n e of t h e s e s c a l e - l e a v e s , a n d
of s e v e r a l of t h e s p o r a n g i u m - l i k e b o d i e s .
T h e sac-like b o d i e s are c o m p a r e d with the s p o r a n g i a of
c e r t a i n P a l a e o z o i c p l a n t s , with w h i c h t h e y a g r e e as r e g a r d s
size, s h a p e , a n d m o d e of d e h i s c e n c e .
T h e closest a n a l o g y ,
h o w e v e r , is found in t h e m i c r o s p o r a n g i u m of the r e c e n t C y c a d s ,
s u c h as Stangeria, of which an e x a m p l e is figured side by side
w i t h o n e of the sac-like b o d i e s .
A l t h o u g h t h e final proof of t h e s p o r a n g i a l n a t u r e of t h e s e
n e w o r g a n s — the r e c o g n i t i o n of s p o r e s — is w a n t i n g , t h e
p r o v i s i o n a l c o n c l u s i o n is a r r i v e d at that t h e y a r e p r o b a b l y of
t h e n a t u r e of s p o r a n g i a a n d w e r e b o r n e on t h e s c a l e - f r o n d s .
T h i s s u g g e s t i o n h a s this merit, that definite o r g a n s , w h i c h in
s i z e , s h a p e a n d s t r u c t u r e h a v e b e e n found to b e not unlike t h e
s p o r a n g i a of certain r e c e n t a n d P a l a e o z o i c p l a n t s , a n d a r e also
a g g r e g a t e d into s o r i , a r e d e s c r i b e d for t h e first t i m e . It is
further p o i n t e d o u t that if t h e c o n c l u s i o n s h o u l d p r o v e to b e
c o r r e c t , it w o u l d s e e m to b e i m p o s s i b l e to r e g a r d Glossopteris
a s a F e r n allied to a n y r e c e n t family of the t r u e F e r n s .
Even
t h e n the t r u e affinities of this plant are b y no m e a n s clear.
S u c h e v i d e n c e as t h e r e is w o u l d t e n d to r e m o v e t h e g e n u s
from p r o x i m i t y to the r e c e n t F e r n s , d e s p i t e its fern-like habit.
Arber (Cambridge).
D. H., T h e S p o r a n g i a of Stauropteris oldhamia,
Binney.
(New P h y t o l o g i s t . Vol. IV.
p . 114—120.
Text
figures 1—2.
1905.)
In this p r e l i m i n a r y n o t e , the fructification a t t a c h e d to t h e
h i g h l y ramified petiole a n d r a c h i s of a c o m p o u n d f r o n d , Stauropteris oldhamia, b e t t e r k n o w n by W i l l i a m s o n s n a m e Rachiopteris oldhamia, Will, is d e s c r i b e d . N o v e g e t a t i v e leaflets
h a v e ever b e e n found in continuity with this r a c h i s ; a fact
w h i c h s u g g e s t s that this frond c o u l d only h a v e b e e n a fertile
o n e . T h e s p o r a n g i a a r e found a t t a c h e d t e r m i n a l l y to the fine,
u l t i m a t e b r a n c h e s of the r a c h i s . T h e c o n n e c t i o n of the b r a n c h l e t
with t h e s p o r a n g i u m h a s b e e n m a d e out, the tissues of the o n e
o r g a n p a s s i n g o v e r quite c o n t i n u o u s l y into t h o s e of the o t h e r .
In form, the s p o r a n g i u m is nearly s p h e r i c a l , in six s p o r a n g i a
m e a s u r e d the a v e r a g e d i m e n s i o n s w e r e 740 ¡.1 X 640 /u. T h e
o u t e r layer of t h e s p o r a n g i u m wall is f o r m e d of s q u a r e or c o l u m n a r cells a b o u t 50 /« in h e i g h t . N o t h i n g of t h e n a t u r e of
a n a n n u l u s h a s b e e n o b s e r v e d , but o n the side o p p o s i t e t h e
SCOTT,