188 ZOOPHYTES. 



Zoophytes, should be effected apparently after the same mode that experi- 

 ment and observation demonstrate as belonging to the Hydraoids. 



During the course of another summer, many specimens, or rather 

 fragments, of the wonted dimensions, towards eight inches long, being pro- 

 cured and introduced into glass cylinders, several globular yellow corpus- 

 cula, such as already described, appeared on the 6th of June. But they 

 also proved inaccessible. The specimens affording them having been re- 

 moved in two days, elongated ovoidal corpuscula, which I concluded to be 

 the preceding now farther developed, were observed swimming in the 

 water. 



Two vigorous specimens being deposited in glass jars on June 13, a 

 number of minute yellow corpuscula lay under one of them next morning ; 

 and on June 16, several were swimming here as elongated ovoids, ten 

 inches above the bottom. By transferring these and others to a suitable 

 position for microscopical inspection, they were found in narrow resem- 

 blance to the planulcB, so often described as among the transitions under- 

 gone in the course of the changes of other animals. They were yellow, 

 smooth, uniform, void of visible external organs under the magnifying 

 powers employed, and endowed with swift, active motion, whether by 

 crawling or swimming in all directions. I could not do otherwise than 

 identify their nature with that of the planula, fig. 11. 



On July 14, two specimens of the Virgularia were lodged in a vessel 

 and removed on the 17th. Corpuscula had issued from them on the 16th, 

 which becoming elongated, continued swimming like planulae in the water. 

 On the 25th, three nascent Virgularise were discovered at the bottom of 

 the vessel, but in such a position that inspection by a lens only could reach 

 them. All lay horizontally. The body of each was elongated cylindrically ; 

 and one extremity inclining upwards, terminated in an asteroid hydra with 

 eight tentacula, figs. 12, 13. 



The mode whereby Nature effected the perpetuation of this zoophyte, 

 was thus ascertained to correspond generally with that of the hydraoid 

 Sertularia : the corpuscula from the adult developing as a planula, attain- 

 ed maturity by the evolution of a terminal hydra. 



From preceding and subsequent inspection, I found a slight adhe- 



