134 Prof. H. James-Clark on the Spongie ciliate 
tific community in regard to the nature of the Sponge. The 
question has been, is it an animal or is ita plant? Bowerbank, 
the highest classificatory authority upon this subject, for a 
long term of years held that it was an animal; but his bases 
for this theory were such that they did not appear to offer a 
satisfactory means of finally deciding the dispute. The latter 
remark applies with equal force to the investigations of Lieber- 
kiihn. Of later years Carter has made some special investi- 
gations in reference to this subject, and in fact he has been the 
first to present anything like decisive proofs of the animality 
of the Sponge. A few words quoted from his paper, which he 
published in the ‘ Annals and Magazine of Natural History ’ 
for April 1857, vol. xx. p. 30, will suffice to show to what ex- 
tent he has carried his observations. Speaking of the “ mono- 
ciliated sponge-cells of the ampullaceous sac,’’ which, he says, 
was set free by the disintegration of the whole mass of the 
sponge, he remarks that ‘“ particles .... were thrown [by the 
flagellum] almost point-blank on its surface, and rapidly passed 
into the interior.” Strangely enough, though, as it seems to 
me now, he does not look upon the intussusception of the 
particles as a genuine process of swallowing, like that which 
obtains among the ciliated Infusoria, but describes it in several 
places, when speaking of the various kinds of sponge-cells, as 
an enveloping of the food after the manner of Ameba. It is 
plain, therefore, that he does not believe that the “ sponge- 
cells’ are endowed with a mouth; and moreover, if I am not 
mistaken, he attributes to any part of the “cell” the faculty of 
engulfing food. This interpretation, therefore, would exclude 
the Sponge from the list of Flagellata, notwithstanding the 
presence of the flagellum. 'That, however, does not weaken 
the proof as to the animality of this organism, but merely * 
leaves it (as Mr. Carter believes it to be) in the most intimate 
alliance with the naked Rhizopoda; and, as if to confirm this 
conclusion, the same authority adds, ‘“'These monociliated 
sponge-cells present the contracting vesicle* in great activity, 
but also in variable plurality.” 1 believe, however, that the 
“variable plurality” of the contracting vesicles does not alone 
belong to the Rhizopoda, but, as I shall show hereafter}, that 
it is also to be observed among the true Flagellata; and I 
would remark, moreover, that when we consider the close re- 
lationship (which I hope to prove in this paper) of the Sponge 
to the other flagellate monad-like Infusoria, which undoubtedly 
* Already noticed by him, in 1847, in the Trans. Bombay Med. and 
Phys. Soc. (abstract in Ann. & Mag, Nat. Hist. 1848). ‘ 
+ Salpingeca marinus, n. sp., § 8, and S. amphoriduum, n. sp., § 9. 
