156 



MAEGELIS CAROLINENSIS. 



IRppocrene superciliaris of the northeast coast, and the Hippocrene 

 Mertensii of the northwest coast, which are differences in the propor- 

 tion of the digestive cavity, its position, the thickness of the bell, and 

 the mode of branchmec of the oral tentacles. 



Margelis carolinensis Agass. 



Margelis carolinensis Agass. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 

 Hippocrene carolinensK McCk. Gymn. Charl. Harbor, p. 62, PI. 10, Figs. 8-10. 



Adult females, taken at Naushon in September, measured about one 

 third of an inch (Fig. 241) ; the main stem of the four oral tentacles 



branches twice, and each of these branches twice (Fig. 242) ; the cav- 

 ity of the bell is small and globular ; the marginal bulbs are large and 

 Fig. 242. conical, and give rise (Fig. 243) to ten or 



twelve tentacles, which are long, slender, and 

 not usually carried curled up tightly near the 

 bulb ; the bulb is colored with brilliant red 

 pigmeni>ceUs, surrounded by a green edge, 

 bordered with bright yellow, and in the yel- 

 low border are placed the black eye-spots, 

 giving to the base of the tentacles a very 

 striking appearance ; the digestive cavity is 

 brick red, and when the folds of the genital 

 glands are expanded by eggs, they hang down in four pouches, so as to 

 hide the peduncle of the digestive cavity. (Fig. 242.) The outline of 



Fig. 241. Adult Margelis, seen in profile ; magnified. 



Fig. 242. Digestive cavity, genital pouches, oral tentacles, and actinostomei 



Fig. 243. Sensitive bulb at base of one of the chymiferous tubes. 



