MELICERTUM GEOKGICUM. 



135 



Melicertum georgicum A. Agass. 



Melicertum georgicum A. Agass.; in Agassiz's Cunt. >«at. Hist. U. S., IV. p. 349. 1862. 



The Medusa (Fig. 215) is here figured to .show t\w diflerences no- 

 ticed between it and the New P]n^land r('})resentative of" the genus. 

 The pointed spherosonie, the smaller number of the cireular tentacles, 

 the longer actinostome, and the termination of the genital organs, 

 somewhat above the circular tube, are characters which readily distin- 

 guish the M. f/eorginnn from its P^astern representative. The knowl- 

 edge of its complete development will settle this point definitely. The 

 close resemblance of the mode of attachment of the ovaries to that 

 of the ^quorida?, referred to in the preceding species, is readily seen 



Fig. 215. 



Fig. 216. 



in Fig. 216. The genital folds are looped up on the upper side of the 

 interior of the bell in an octagonal outline (Fig. 216), opening into the 

 large cavity formed by the eight constrictions of the hps, /, of the acti- 

 nostome. The difference is simply in the number of the chymiferous 

 tubes, as well as in the mode of carrying the lips of the actinostome. 

 A simple flattening of the spherosome, and an increase in the number 

 of chymiferous tubes, would give us an ^quorea. This Medusa is 

 found, in the summer, in the Gulf of Georgia, W. T. 



Fig. 215. Profile of Melicertnm georgicnm, natural size. 



Fig. 21 G. Digestive cavity and point of junction of the chymiferous tubes. L lips of actinos- 

 tome ; jD, abactinal point of attachment of genital organs ; c, opening leading into chymiferous 

 tubes. Magnified. 



