ON THE EOE]\IATION OE THE EOG IN THE ANNULOSA. 
597 
Leucbaet* has already noticed a remarkable vesicle which was observed by him in 
the yelk of GeopTiilus. I have not convinced myself as to the presence of any such body 
in that genus, but have observed a vesicle constantly present in the yelk of Arthronomalus, 
a genus which is closely allied to Geophiliis^ and which was probably the subject of 
Leuckaet’s examination, A smaller vesicle, probably however of a similar nature, also 
occurs in lAthobiiis, and a still more rudimentary structure also appears to exist in lulus. 
In Glomeris, as already mentioned, vitelligenous cells, not unlike those of Coccus^ are 
present. 
Chilogjstaths. 
Glomeris marginata., Plate XVI. figs. 1, 2, 3. — In this species, and probably in all 
the Chilognaths, there are two \ailv8e, which are situated in the third segment, and 
open into two short egg-canals. These soon unite into a common oviduct, which 
again in its turn quickly expands into a large, simple, cylindrical ovary. This ovary 
extends in a straight line back nearly to the posterior pair of legs, and lies imme- 
diately below the intestinal canal. It is extremely delicate, and so transparent that 
it might easily be overlooked if it was not rendered conspicuous by the opake white- 
ness of the eggs contained in it. These, however, are not produced indiscriminately 
over the whole surface of the ovary, but only along two ribbon-shaped parts which run 
along the lower lateral portions of the ovary, almost from one end to the other, and thus 
leave the whole of the upper wall of the ovary, the sides, and a narrow strip along the 
middle of the ventral surface quite free from eggs. When the egg-germs are still quite 
small, these two “stromas” have the appearance of two separate ovaries; and it is 
probable that, as M. Fabke has suggested in his excellent memoir “ Sur I’anatomie des 
organes reproducteurs et sur le developpement des Myriapodes f ,” it is from having 
examined the animal at this stage, and from having overlooked the ovarian walls, that 
the earlier observers were led to describe the organ as being double 
The follicles in which the eggs are developed also probably contributed in no small 
degree to this eiTor, since they do not project, as one would naturally expect they would 
do, from the outer surface of the ovary, but, on the contrary, protrude into its central 
cavity ; so that even if the delicate walls of the ovary are perceived, they may easily be 
mistaken for a band of some tissue intended to keep the two supposed ovaries in their 
place. The walls of the follicle consist of nucleated epithelial cells (Plate XVI. fig. 1), 
- and each follicle contains only a single egg. The follicle is at first small, but grows 
in size as the egg-matter contained in it increases in volume, and takes an elongated 
* Art. Zeutmi!". t Annal. des Sci. Nat. 1855. 
+ See Teetieaxits, Verm. Schr. p. 45, who, however, has correctly seen the two strings of eggs ; Beandt, 
MuLnEE’s Archiv, p. 8.37 ; and Steix, Muleee’s Archiv, 1842, p. 248. M. Eabee, though he has cor- 
rectly explained the relation of the different parts, still describes the ovary as double, since he denies the 
name of ovary to the central sac, and applies it only to the two stromas, in which, according to him, the eggs 
are formed. It is not, however, quite correct to say that the eggs are formed in the stromas, since in reality 
they arise in follicles which are only attached to the stroma by their base. 
4 M 2 
