52 
F. IV. Oliver . 
certain dubious structures recently found in the surface layers of 
the nucellus of what is probably a second species of Stephano - 
spernium. 1 The bodies in question lie at the surface of the nucellus 
everywhere between the pollen-chamber and the chalaza. The 
sketch of part of a tangential section of the nucellus of this seed 
(Fig. 7) shews the nucellar epidermis (e) detached from the under¬ 
lying parenchyma (up) within which follows the tracheal mantle (/). 
Finally the wall of the macrospore (line). Lying here on the nucellar 
parenchyma are these small ovoid bodies (a, b &> c) which are 
perhaps referable to a fungus like Grilletia. The average 
dimensions of these little vesicles is 23a x 16/x. Further details 
of their structure are given in figs. 8, 9 and 10. Each vesicle is of 
ellipsoidal outline and shews a considerable degree of flattening 
upon the nucellar parenchyma. The examples represented in figs. 
8 & 10 are typical. Each is represented lying on the crushed 
parenchyma of the nucellus, whilst a portion of a tracheide is 
also given in fig. 8. In the middle of the convex face of the vesicle 
an oval area is generally present symmetically divided along its 
major axis by a slit-like line (figs. 8 and 10). The bodies by 
themselves are difficult of interpretation, especially as no traces of 
connecting hyphae are present. Until the frequency with which 
Grilletia -like fungi occur in this actual situation was realised, it 
seemed possible the bodies might even belong to the nucellus. 
However, the most reasonable view of their nature seems to he that 
they are the sporangia of some fungus of similar nature. 
A comparison has been drawn between Grilletia and the 
Chytridineae. If we turn to that group, forms are not lacking in 
which the sporangia hear specialised opercula connected with the 
discharge of the swarm-spores. This is the case for instance in the 
genera Chytridium , Tetrachytrium and Zygochytrium, 3 The curious 
pore-like appearance seen on these vesicles may possibly indicate 
the presence of an operculum which has become, perhaps owing to 
the confined position, partly pressed into the sporangium. One of 
these bodies is represented in fig. 9 with its convex surface partly 
ground away. The slit-like furrow (?) is still apparent, so that it 
may be inferred that this portion of the mechanism projected an 
appreciable distance into the vesicle. The whole structure, it may 
he conjectured, was a sporangium with an operculum of oval 
contour, in which, owing to the circumstance of its development, 
1 S. caryoides, as yet undescribed, also from Grand ’Croix. 
2 Scliroter, Chytridineae in Rngler and Prantl, Die naturlichen 
Pflauzenfamilien, I Teil, i Abt., pp. So, 8^ and 87. 
