122 Mr. H. J. Carter on the Circulation of the 



toplasm^ apparently of adjustment, took place. It then assumed 

 a globular and afterwards an ovoid shape, when the small end 

 becoming transparent and throwing out a wreath of active cilia, 

 it bounded off and was soon undistinguishable from other spores 

 of the same kind which were present in equally active motion. 

 At the moment of its exit I observed a delicate membrane at 

 some distance around it which disappeared (by bursting ?) im- 

 mediately the cilia began to play. 



Having thus brought forward incontestable proof of loco- 

 motive power in structures homologous with the mucus-layer of 

 the cell in the Characese, I shall now only add another instance 

 of the kind mentioned (p. 19), where a partial movement of 

 the mucus-layer, again in Chara verticillata, afforded direct evi- 

 dence of its possessing the independent power of contractility 

 in question. This occurred in a very young plaut where the 

 roots were nearly an inch long, though not more than the 500th 

 of an inch broad, and, as before stated, as transparent as glass. 

 While tracing one of these, in which the circulation appeared to 

 have ceased, I came to a part where there was a slight move- 

 ment of the mucus-layer, which increased up to a certain point, 

 and then as gradually subsided again. It was a thickened 

 portion, but apparently composed of nothing more than trans- 

 parent mucus charged with a number of granules. It was 

 moving towards the extremity of the root, and was seen to pass 

 through that part of the latter which was kept in the field of the 

 microscope for the purpose, leaving all the mucus as still behind 

 it as that which was beyond the moving portion. To conceive 

 after this that the mucus-layer of the Characese is endowed with 

 a locomotive power, seems not difficult, if we cannot conclude 

 that by this power also it moves round the iuternode. 



Since the above was written, I have read the following pas- 

 sages in Cohn's ' Natural History of Protococcus pluvialis ' 

 (1850), translated by Busk for the Ray Society {loc. cit. p. 532, 

 1853), and they so accord with my own conclusions on the sub- 

 ject, that I cannot do better than insert them here, as a termi- 

 nation to an argument in favour of the moving power of the 

 mucus-layer or protoplasmic cell of the Characeae, instituted for 

 the purpose of conveying a similar impression : — 



" From these considerations it would therefore appear, as cer- 

 tain as it can be made by an empirical deduction from the pre- 

 mises in such a subject, that the protoplasm of botanists and the 

 contractile substance and sarcode of zoologists, if not identical, 

 are at all events in the highest degree analogous formations. 



" Whence, the distinctions between animals and plants viewed 

 in the above light must be thus understood : that in the latter 

 the contractile substance, as the primordial utricle, is enclosed 



