94 ZOOPHYTES. 



the subject more evident ; whence the Cristatella must be classed with 

 nocturnal animals. 



It seems also to be of solitary habits. 



All the compound zoophytes that is composed of hydrse along with 

 the polyparium, such as specified in the preceding pages, manifestly de- 

 cline on the permanent retreat of the animals. Though covered at first 

 by thousands, leaving scarcely an atom of the surface vacant while in 

 vigour, fewer and fewer at length appear spontaneously, and that in pro- 

 portion to the time of preservation, nor is the renewal of their element 

 effectual in eliciting them to the light. 



Here, as the hydrse cease to unfold, the substance of a specimen be- 

 comes somewhat thicker, and is greatly contracted on the whole. Yet, even 

 after the entire colony has continued in pertinacious and protracted re- 

 treat, the specimen shifts its site, thus demonstrating, as I apprehend, 

 that progression does not result from volition of the numerous hydrse, 

 whose activity seems concomitant only on the display of their own organs. 



In as far as circumstances have enabled me to judge, the life of the 

 Cristatella does not exceed a single year. This is a difficult point, indeed, 

 whereon reserve is necessary. Perhaps, however, it is limited to six or 

 seven months. One of the hydrse of an adult specimen survived during 

 nine weeks. That specimen was much contracted ; its skin had become 

 very tough and elastic — yielding on pressure. 



Perpetuation. — This important part of animal physiology offers some 

 peculiarities, which it has not been my lot to witness in any other product 

 of the creation. Though fulfilling the general rule devised by the Author 

 of Nature, for the preservation of the race, and the continuance of life, its 

 difference from the ordinary progress of evolution, merits our highest admi- 

 ration. Singular it is, that those minute objects, passing unheeded by 

 ignorant and thoughtless mankind, should manifest a power reserved for 

 Omnipotence only. Ought we not to be humbled in all our pride of pre- 

 eminence, on reflecting that the ablest among us, far from the faculty of 

 forming an original atom, cannot even comprehend how that atom is 

 formed : and, although beholding the evolution of animated matter ad- 



