H. A. Baylis 
365 
runs forward in close connection with the mid-ventral line of the body- 
wall, to open between the two rudimentary ventro-lateral lips (PI. XVI, 
fig. 1, E.). This organ has been fully described by Stewart (1906), 
who has carefully studied its histological nature. It is unnecessary, 
therefore, to dwell upon it here, except to point out that it is a prominent 
characteristic of the species, and occurs not only in the larvae, but in 
the adult Ascaris decipiens. Yon Linstow (1884) seems to have confused 
this excretory gland of A. capsularia with the “ Drusenschlauche” or 
“ Blinddarmer,” of which he says (erroneously, in my opinion) there 
are two. His figure (PL VII, fig. 5, d, e ) seems to show clearly that what 
he saw was the excretory cell. 
I have not observed any indication of the development of genital 
organs in any of the larval stages examined. 
The larvae undergo at least two ecdyses within their surrounding 
capsules, which are presumably formed by a morbid hypertrophy of 
the peritoneal tissues of the host. The cast-off cuticles are not com¬ 
pletely got rid of by the larva until it is liberated from the capsule, but 
expand so as to form an additional loose protective sheath or sheaths, 
one within the other, and permit of the continued growth of the larva 
within them. 
Ascaris decipiens Krabbe. 
(PI. XIV, fig. 4; PI. XV, fig. 1; PI. XVI, figs. 3-4.) 
Krabbe (1878), p. 45; PL I, fig. 3. 
Jagerskiold (1894), p. 467; PI. XXV, fig. 14; PI. XXVI, fig. 26; PI. XXVIII, 
figs. 40, 41. 
Stiles and Hassall (1899), p. 109; Figs. 1-19. 
Ascaris simplex, von Linstow (1888), p. 2; PI. I, figs. 1—4. 
The present observations on the adult form are based upon a re¬ 
examination of specimens from Otaria jubata obtained at Kerguelen 
by the Challenger, and determined by von Linstow as Ascaris simplex 
Rud. This seems to have been a misdetermination, though it is difficult 
to understand how so experienced a helminthologist was led to make the 
error. At that time, however, the description of A. decipiens given by 
Krabbe was the only reliable and at all detailed account available, 
and the characters of the bps, alimentary canal and other important 
systematic points had not been so accurately figured and described 
as has now been done, owing to the careful work of the later 
authors. 
