74 Natural History of British Zoophytes. 



ture — the tenements and products of animals similar in many respects 

 to the naked fresh-water polype. By examining them, in a living 

 state, through an ordinary microscope, he saw these polypes in the 

 denticles or cells of the zoophyte ; he witnessed them display their 

 tenacula for the capture of their prey, — their varied actions and 

 sensibility to external impressions, — and their mode of propagation ; 

 he saw further that the little creatures were organically connected 

 with the cells and could not remove from them, and that although 

 each cell was appropriated to a single individual, yet was this unit- 

 ed " by a tender thready line, to the fleshy part that occupies the 

 middle of the whole coralline," and in this manner connected with 

 all the individuals of that coralline. The conclusion was irresisti- 

 ble — the presumed plant was the skin or covering of a sort of mini- 

 ature hydra, — a conclusion which Ellis strengthened by an exami- 

 nation of the covering separately, which, he said, was as much an 

 animal structure as the nails or horns of beasts, or the shell of the 

 tortoise, for it differs from " sea-plants in texture, as well as hard- 

 ness, and likewise in their chemical productions. For sea-plants, 

 properly so called, such as the Algae, Fuci, &c. afford in distillation 

 little or no traces of a volatile salt : whereas all the corallines afford 

 a considerable quantity ; and in burning yield a smell somewhat re- 

 sembling that of burnt horn, and other animal substances ; which 

 of itself is a proof that this class of bodies, though it has the vegeta- 

 ble form, yet is not entirely of a vegetable nature."* 



Ellis taught no novel doctrine, but he gave it fixidity and curren- 

 cy ; and he moreover applied it to those very zoophytes which pos- 

 sessed the vegetable appearance in the most perfection, many of 

 which he was the first to notice, and which he illustrated with a se- 

 ries of figures of unequalled accuracy.t He rarely went beyond the 



* Dr Good is in error when he states that the ammoniacal smell from burnt 



zoophytes was the principal fact for placing them in the animal kingdom Book 



of Nature, i. 175 and 210. 



f As mentioned above, Bernard de Jussieu knew that the Sertulariadae — the 

 zoophytes here alluded to — were animal productions, but no detailed account of 

 his observations seems ever to have been published. Trembley had made the 

 same discovery. Dr Watson, in his account of Peyssonnel's treatise in 1752, 

 tells us that Mr Trembley shewed him, " at the late excellent Duke of Rich- 

 mond's," the small white polypes of the Corallina minus rarnosa alterna vice den- 

 ticulata of Ray, " exactly in form resembling the fresh-water polype, but infinite- 

 ly less." " When the water was still, these animals came forth, and moved their 

 claws in search of their prey in various directions ; but, upon the least motion 

 of the glass, they instantly disappeared." P. 463. — Linnaeus, however, in refer- 

 ence to the observations made previous to Ellis, says they are " inchoatae, non 

 ad plenum confectae, et desiderentur adhuc quam plurima, quae dies forte reve- 

 labit." — Amoen. Acad. vol. i. p. 186. 



