238 ZOOPHYTES. 



discovered between the articulations and the cells ; there is no definite cor- 

 respondence in number or extent. 



A hydra, with a pencil of 16 or 18 tentacula, rises within, to display 

 them from the orifice of the cell, which is so transparent as to expose its 

 almost colourless, long, tapering body, afiixed by ligaments to a remote 

 point below, figs. 8, 9. One or two fine vermilion ovular substances are con- 

 tained in the body of many, rising and falling along with it. Their na- 

 ture has not been explained. — Fig. 4. Numbers are free of them. The 

 hydra is alike lively as others, clasping its tentacula together when dis- 

 played, exercising them in percussive action, with all the peculiarities dis- 

 tinguishing the vigorous tenants of ascidian zoophytes. 



The stem should consist of aggregated tubuli, to judge by the shoots 

 sent forth of the extremity, when sundered. At least 15 filamentous pro- 

 longations issued downwards from a section, ultimately extending much 

 farther in proportion than represented in fig. 10, and adhering to the ves- 

 sel wherein deposited. Meantime the opposite extremity was vigorously 

 regenerating hydrse within, and the avicularium without the cells. 



All the higher parts are regenerated, as may be seen from different 

 specimens, in various stages, where the colours are contrasted. The re- 

 generations are of the palest grey, almost or entirely white. — Figs. 5, 6, 7. 

 This product occurs at an early period as a single stalk, not a line in 

 height, with its hydra displayed. Another hydra is generated, in the next 

 place, on the same side, and then a third still higher. The final modifica- 

 tion and arrangement of the parts belong to a later era. 



A white, opaque globule rested on the oi-ifice of several cells of a 

 specimen obtained in the beginning of INIarch, during survivance of living 

 hydrte on other parts. Active avicularia, of which more particularly here- 

 after, were also dispersed over it. — Fig. 11. 



Specimens are frequently stained with red patches. If any be at 

 first pale, they become soon deep coloured : the hydrfe are found dead, and 

 the avicularia motionless. Those thus distinguished are very beautiful. 



The parts intercept each other so much, and are so numerous, that the 

 smallest fi-agments only can be taken for microscopical observations. 



This zoophyte is always rooted on solid substances. It is not common. 



