248 Mr.H.J. Carter on a Variety of Spongilla Meyeni. 
Obs. 'This Spongilla chiefly differs from Sp. Meyent of Bom- 
bay in the decidedly spinous character of one-third of its largest 
spicules, while about the same proportion in the Bombay spe- 
cies can be only termed “ incipiently spinous.” The excess in 
size of the elementary parts generally of the Bombay species 
over those of the variety in the river exe amounts to nothing, 
specifically considered. | 
But there is a much more decided difference between var. 
Parfitti and the birotulate English species termed Sp. fluviatilis, 
which also grows in the river Exe, inasmuch as the spicules 
of the skeleton in the latter are all smooth, the shaft of the 
birotules, somewhat constricted in the centre, approaching to 
hour-glass shape, with the margin ondy of the rotules minutely 
dentate, almost fringed *. 
I am indebted to my intelligent friend, the able naturalist of 
Exeter, Mr. HK. Parfitt, for having brought to my notice the 
existence, in the river Exe, of the variety and species of 
Spongilla above mentioned, where this gentleman found them 
some time since; and, he having kindly submitted them (in the 
dry state, with his own notes of what they were when alive) 
for my examination and publication, I cannot do better than 
dedicate the variety to him. 
The indistinct colour of var. Parfitt? may perhaps be attri- 
buted to the filtering position in which it grows, viz. on the 
beam of the weir over which the Exe falls at the Salmon-pool, 
if not also the more spinous state of its spicules generally ; 
while the position of Sp. fluviatilis, taken from the Canal and 
parts of the Exe just above, where Mr. Parfitt found it incrust- 
ing the stems and leaves of Anacharis and on hard substances 
respectively, presents not only the usual fawn-colour of Sponges 
in general, but also a less spinous state of the spicules—per- 
haps from a less agitated state of the water in which it 
rows. 
: IT still adhere to the term ‘seed-like body,” instead of 
adopting that of ‘ ovary,” used by Dr. Bowerbank ; for where, 
literally, we cannot yet make “head or tail” of an organism, 
it certainly is premature to designate any part of it by a term 
which is essentially connected with the true process of genera- 
tion. Moreover I have already pointed out the identity in 
structure and composition of the seed-like body of Sp. Cartert 
with the winter-egg of the Bryozoat; and I am pleased to 
find just now, by chance, that Meyen, long before this, had 
* See also Dr. Bowerbank’s figures and descriptions, Proc. Zool. Soe. 
Lond. Nov. 24, 1863; and Ray Soc. publ. 
+ Annals, 1859, vol. iii. p. 331, 
