358 Mr. H. J. Carter on Spongiophaga Pottsi. 
the statoblast, which is always open at its free end, may be in 
part produced by the sponge itself, to sure, if possible, a sate 
egress for the reproductive particles against the rapacity of its 
unwelcome visitor; while the passage of these particles en 
masse into the lower and dilated cavity of the filament, with 
their presence some way on, arranged linearly in the axial 
canal, together with the corrugation or transverse strize on the 
surface, much more resemble the features of a filiform or 
nematoid parasite than any thing belonging to the vegetable 
kingdom—especially when, after inferring that the fixed end 
is the oral extremity, we find the filament gradually dimi- 
nishing into an attenuated whip-like form which is terminated 
by a curved and pointed element like that of many Filariide. 
The marine species called by Lieberkiihn ‘“ Faden,” by 
Schmidt “ Fibrillen,” by Schulze “ Filamente,” and by myself 
Spongiophaga communis, has been latterly pointed out by 
Schmidt to have a bulb at each end, in a communication 
entitled “‘ Die Fibrillen der Spongien,” of which he kindly sent 
me a copy on the 15th May, 1878, just before my ‘ Parasites 
on the Spongida’ was published; so that I ought to have 
mentioned it therein. Hence to atone for this accidental omis- 
sion, in priority, as I had discovered the same thing myself 
independently, it is here thus mentioned. (Whence the 
“separate copy ’’ of Schmidt’s paper is extracted, however, I 
cannot say; forit only bears the pagination, viz. 661.) Sub- 
sequently Prof. F. EH. Schulze of Gratz studied Spongio- 
phaga communis in his usual exhaustive manner (Zeitschrift 
f. wiss. Zoologie, Bd. xxxiii. 1879, ‘“ Untersuchungen &c. 
Die Gattung Hircinia, Nardo, &e.,” Taf. iv.) ; and under the 
heading of “ Die Filamente” (Separat-Abdruck, p. 23) he 
states that the filaments present no trace of cellulose, and have 
not, apparently, been found through chemical analysis to agree 
in composition with the horny fibre of the official sponge ; 
while further observations are necessary to determine what their 
real nature is, although they may be assumed to be foreign 
organisms growing and thriving in the sponge. However, in 
his fig. 4, Taf. iv. (loc. cit.), there is a fragment delineated 
with a transversely corrugated exterior and a central cord 
(‘¢ Achsenstrang,” p. 21, oc. c7t.), which to a certain extent 
corresponds with what 1 have stated to be presented by the 
proximal part of the filament of Spongiophaga Pottst. 
Lastly, as regards the specimen of Spongtophaga Pottst in. 
Meyenia Bailey, Bk., from Buffalo, which Mr. Potts in his 
letter states to have been sent to him by Mr. H. Mills, the 
development seems to have only just commenced; for the 
filaments to the number of from two to four rising from the pro-~ 
