HYDEA. 97 



VI. As the offspring withdraws from the parent, a connecting liga- 

 ment is gradually attenuated, and at length ruptured, as in certain species 

 of the Actinia. 



VII. If rupture of the ligament be protracted, cotemporary progeny 

 may continue budding, both from the body of the parent and from that of 

 the offspring. 



VIII. The elements of the progeny are not concentrated in a definite 

 spot of the body of the parent. 



IX. The hydra is very tenacious of life ; it is endowed with power- 

 ful regenerative energies. It survives the severest wounds and lacerations, 

 and reproduces mutilated parts. 



X. It is endowed with a locomotive faculty, which is very rarely ex- 

 ercised by adults ; and chiefly demonstrated by the young. 



XI. Its natural and favourite position is suspension by the apex, al- 

 lowing the free extension of the tentacula. 



XII. It dwells in numerous societies, or lives in a solitary state. 



Plate XIII. Hydra tuba. Trumpet Polypus (Strolila). 

 Fig. 1. Adult ; body, a ; tentacula, I. 



2. Colony investing an old shell of a Serpula. 



3. Adult, a ; embryo budding from it, b, spur. — April 27. 



4. The same farther advanced ; adult, a ; embryo, h ; spur, c. 



—May 8. 



5. The same ; embryo, I ; spur, c ; both now perfect hydne, 



still connected with the parent, a. — May 25. 



6. The same augmented by new gemmation ; the offspring 



withdrawing from the parent. 



7. The same colony farther dispersed. As a, 5, c, here, and 



of the preceding figure separated, new animals, d,f, i, 

 were interposed. — June 12. 



8. The same colony, consisting of eight perfect hydrse, besides 



embryos. — July 7. 



9. The same according to its final arrangement and aspect 



while remaining in distinct view. Some hydra, previously 

 single, d, i, have now generated others, d, i. — July 21 . 

 VOL. I. N 



