CAMPANULARIA. 225 



in October and November. It is very minute, not extending the third of 

 a line, of vivid green colour, and at first of the wonted habits, form, and 

 aspect. 



But instead of being generated within a pod or vesicles as others 

 from the hydraoidal Sertularise, its matrix consists of a congeries of cavities 

 or compartments, as seen in the surface of the mass. — Fig. 5. An aperture 

 being discovered in the middle of each after the planula has been dis- 

 charged, we may presume that no more than one is contained in a com- 

 partment. — Fig. 6. 



These animals are extremely numerous ; at least 150 quitted a speci- 

 men during the last days of October and the beginning of November, — all 

 concentrating soon in a watch-glass. 



When fresh and vigorous they are not distinguished by any noted 

 peculiarities, nor until in early preparation for the usual metamorphosis. — 

 Fig. 7. But important changes ensue as this advances, and they are such 

 as I have not witnessed in any other of the tribe. When the planulse are 

 about to remain stationary, the body becomes round and deeply annulated, 

 exhibiting a number of prominent segments, like the whirling lately de- 

 scribed as indenting the stems and branches of zoophytes. Then they 

 have much the appearance of minute green leeches, excepting in the rings, 

 their vivid green colour being still preserved. — Fig. 8. 



In a short time one end of the planula forms an enlargement, while 

 the other is elongating. — Figs. 9, 10. A bud swells above, fig. 11, which 

 rising as a long cell, shews an internal hydra under different aspects in 

 progressive evolution. — Figs. 12, 13, 14. At length the whole organic 

 structure being perfected — the animal is completely unfolded. — Fig. 15. 



As the hydra advances, two rings enlarge the body near the root, 

 and the origin of the head, which afterwards disappear on the attainment 

 of greater maturity. The lower extremity of each subject seems affixed 

 below ; the higher rises in a clavate form. 



The concentrated multitude, fig. 15, in as far as can be observed, 

 does not consist of so many hydrse incorporated together, or united to any 

 common substance, in such a manner as to be compared, for example, to 

 the Flustra, all seem to be only in approximation. 



VOL. I. 2 F 



