Microscopical Society. 3339 



Proceedings of the Microscopical Society of London. 



November 26, 1851. — Dr. A. Faeee, President, in the chair. 



Dr. Carpenter detailed the results of some observations made by Mr. Williamson, 

 of Manchester, on Volvox globator. He stated, that, startling- as the assertion might 

 at first sight appear, Mr. Williamson had come to the conclusion that the Volvox be- 

 longs not to the animal, but to the vegetable kingdom ; and that he himself, having 

 gone over the evidence, was inclined to concur in this view. The increase of the cells 

 (from the supposed ova) being carried on in a manner precisely analogous to that of 

 undeniable Algae ; while many of the so-called polygastric animalcules of Ehrenberg 

 having been proved zoospores of some of the Confervas, renders the supposition pro- 

 bable. It appears, from Mr. Williamson's observations, that between the outer inte- 

 gument and the primordial cell-wall of each cell, a hyaline substance is secreted, caus- 

 ing the outer integument to expand ; and as the primordial cell-wall is attached to it 

 at various points, it causes the internal colouring matter, or endochrome, to assume a 

 stellate form, the points of one cell being in contact with those of the neighbouring 

 cell ; these points forming, at a future period, the lines of communication between the 

 green spots so often noticed on the adult Volvox. Dr. Carpenter argued that the evi- 

 dent automatic action of vibratile cilia was also in favour of the vegetable theory ; 

 and cited a case in which a cistern that had been recently cleared out, and partially 

 filled by the rain only, had become suddenly and rapidly covered with a bright green 

 scum, which on examination proved to be the Cryptomonas of Ehrenberg. The water 

 could have contained nothing in solution, with the exception of perhaps a little car- 

 bon ; and Dr. Carpenter thought that the distinction between the animal and vegeta- 

 ble kingdoms could be better defined by having regard to the nutriment than by any 

 other mode, — animals requiring organized matter for food, while vegetables flourish 

 on inorganic matter, or else organic matter in a- state of decomposition. 



Mr. Bowerbank rose, not to oppose Dr. Carpenter's view, but to ask some ques- 

 tions in order to elicit further information. Was it an established fact that there were 

 cilia, or was their presence merely inferred from the motion? Was there any discharge 

 of the contents of the primordial cell, — and if so, was the contraction sudden or gra- 

 dual ? He had witnessed a similar appearance in the early cells of some of the ferns, 

 in which it was assumed in consequence of the sudden ejection of the contents, — and 

 he appealed to Mr, Deane, who had paid much attention to the development of the 

 ferns in the earliest stages. 



Mr. Deane stated that he conceived Mr. Bowerbank had misapprehended Dr. Car- 

 penter's statement ; as the stellate appearance in the cells of the Volvox was owing to 

 the dilatation of the outer integument in consequence of the formation of hyaline sub- 

 stance, while the appearance in the ferns was owing to the contraction of the inner 

 membrane. There was no doubt of the existence of cilia in the mature Volvox. 



Mr. Shadbolt could speak distinctly as to the presence of cilia in the Volvox ; al- 

 though difficult to see while the creature was in motion, they could be readily observed 

 by confining it, and still more so by compressing and rupturing the sphere, by which 

 means, at the torn edges, they could even be counted. He was not yet prepared to 

 coincide with the vegetable view ; aud reminded Dr. Carpenter that the automatic 

 nature of the movements could not be considered as any argument in favour of a 

 vegetable theory, as it was precisely analogous to the automatic retraction of the ten- 

 tacula in the Bryozoa. His chief objection, however, was, that the Volvox presented 



