132 ZOOPHYTES. 



Plate XX. Fig. 7. The same enlarged. 



8. Bulb become a hydra, with extending tentacula, from which 



all the Medusae composing the embryonic column, but 

 three or four, had been liberated. 



9. The same a week later, developed into nearly a perfect 



hydra, all the Medusae being liberated ; a spur, c, from the 

 side. 



10. The same in 46 days from the appearance of fig. 8. A 



young hydra, h, having been generated from fig. 9, a, now 

 appearing as 5, in this fig. 10. 



11. Vegetation proving unproductive from the base of fig. 10, a, 



enlarged. 



12. The subject a, figs. 2, 3, now become a perfect hydra ; natural 



size. 



13. The same with indications of gemmation. 



14. The same five days later, a ; with its offspring, h. 



15. A specimen undergoing progressive change. Bulb, a; co- 



lumn of Medusae advancing, c ; crowned by a circle of ten- 

 tacula, h ; another circle, d, developing from the bulb. 

 Embryo budding, e. 



16. The same a week later. The former coronet, 5, of fig. 15, 



obliterated ; Medusae come to maturity ; tentacula from 

 the bulb advancing, c ; embryo, e, of fig. 15, having ac- 

 quired tentacula. 



17. The same a week later, now free of Medusae ; embryo im- 



proved ; gemmation indicated from the parent hydra, a. 



18. The same in three weeks ; embryo budding, and young hydra 



having withdrawn from the parent. 



19. The same as seen 48 days subsequent to the appearance of 



fig. 15, the family consisting of five independent indivi- 

 duals. 



20. The subject, (figs. 11,12,) 28 days later, now consisting of a 



symmetrical hydra. 



21. The same in a fortnight, with its progeny. 



22. The same 57 days later than figs. 11, 12, now a family of 



seven independent individuals. These are somewhat con- 

 centrated in the drawing, being much dispersed on a watch- 

 glass. 



