MEMOIRS 



READ BEFORE THE BOSTON SOCIETY OF NATURAL HISTORY. 



VOLUME I. PART III. 



IX. On the Spongke Ciliatse as Infusoria Flagellata ; or, Observations on the Structure, Ani- 

 malitg, and Relationship of Leucosolenia botryoides, Boiverbank. 1 By H. James-Clark, 

 A. B., B. S. Professor of Natural History in the Agricultural College of Pennsylvania. 



Read June 20, 1866. 



HAVE been engaged, like others, for some time past, endeavoring to clear up the 

 doubt which prevails in the scientific community in regard to the nature of the Sponge. 

 The question has been, is it an animal or is it a plant ? Bowerbank, the highest classifica- 

 tory 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 investiga- 

 tions of Lieberkiihn. Of later years Carter has made some special investigations in refer- 

 ence to this subject, and in fact he has been the first one to present any thing like decisive 

 proofs of the animality of the Sponge. A few words quoted from his paper, which he pub- 

 lished in the " Annals and Magazine of Natural History " for April, 1857, Vol. xx. p. 30, will 

 suffice to show to what extent he has carried his observations. Speaking of the " monocili- 

 ated sponge-cells of the ampullaceous sac," — which he says was set free by the disintegra- 

 tion 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 intussuscep- 

 tion 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 Amoeba. 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, notwith- 

 standing 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 RMsopoda ; and, as if to confirm this conclusion, the 

 same authority adds, " These monociliated sponge-cells present the contracting vesicle 2 in 

 great activity, but also in variable plurality." I believe, however, that the " variable plu- 



i A sketch of the contents of this memoir has already been 2 Already noticed by him in 1847, in the Trans. Bombay 

 published in the Proceedings of this Society for June 20, 1866 ; Med. and Phys. Soc. ; abstract in Annate Mag. Nat. Hist., 

 and in the American Journal of Science for November, 1866. 1848. 



MEMOLHS BOST. SOC. NAT. HI9T. Vol. I. Pt. 3. 1 



