33 



and ulva, and occasionally changed by carefully adding a 

 quantity taken from the natural habitat of the medusa in 

 the eel pond. A low temperature was maintained. When 

 these larvae were received from V/ood's Hole, November 28, 

 they were apparently thriving well. They were settled upon 

 Minot watch glasses which were easily removed from the 

 aquarium- jar without disturbing their contents. These 

 dishes were numbered and the positions of the polyps care- 

 fully noted and mapped. Successive examinations shov/ed 

 that the number of polyps was on the increase, and, on De- 

 cember 3, it was seen that one or two ol' the largest spec- 

 imens had rounded knob -like bodies upon their surfaces, 

 which were recognized as buds. These specimens were exam- 

 ined as frequently as it was thought safe to remove them 

 from the jar, and camera drawings were made of the growing 

 buds. Observations were made of the different stages in 

 the development of fourteen buds; their phases agreed in 

 all the main particulars. 



The first indication of the appearance of a bud upon 

 any individual polyp v/as seen as a rounded eminence upon 

 the hydrocaulus (Fig. 15, b). It was usually located at a 

 level about half way between the base of the polyp and the 



