MUSEUM OF COMPAKATIVE ZOOLOGY. 237 



These tentacles are similar in general features to those of our common^, super- 

 ciliaris (Agass.). At the base of each tentacle, upon the ventral (inner) side, 

 there is a dark purple pigment spot or ocellus, which projects a little from the 

 general level of the ectoderm as a conical protuberance. The velum is well 

 developed. Upon the lips of the manubrium one also finds four bunches of 

 tentacles. These manubrial tentacles arise from the lips of the manubrium 

 as four main stems ; each of these stems branches dichotomously four times, 

 thus giving rise to sixteen tentacle tips from each lip of the manubrium. These 

 tips are slightly knobbed, and are composed chiefly of nematocyst cells. The 

 manubrial tentacles are very flexible, and may be observed waving gracefully 

 to and fro within the cavity of the bell. By far the most remarkable feature 

 of this specimen is the presence of numerous medusa buds springing from the 

 gastric region of the manubrium. These medusa buds were arranged in four 

 radial clusters, and contained individuals in various stages of development. I 

 do not doubt that they become free, and thus the race is propagated asexually 

 in the medusa stage in a manner very similar to that of the Dysmorphosa ful- 

 gurans (A. Ag.) found at Newport. So far as I am aware, this is the first 

 species of the genus Bougainvillia which has been observed to reproduce in this 

 manner. The color of the digestive portion of the manubrium, and of the basal 

 bulb of the tentacles is rosin-yellow. 



Two new and very interesting genera of Hydro-Medusge, clearly belonging to 

 the subfamily Irenidae as defined by Haeckel in his " System der Medusen," 

 pp. 167, 199, etc., were found during the cruise. Haeckel defines the Irenidse 

 as a subfamily of the Eucopidse distinguished by the possession of numerous 

 otocysts (12-16 or more) and a distinct gastric peduncle. In these new medusae 

 the peduncle of the manubrium is much less developed than in any hitherto 

 known genus of the Irenidae. There are twelve interradial otocysts, and the 

 four genital glands develop in restricted regions on the radial canals near the 

 manubrium. We have given them the names Cubaia Aphrodite and Ireni- 

 opsis primordialis. 



\ 



Cubaia Aphrodite, nov. gen. et sp. 



Plate II. Figs. 1, 3, 3. 



This very beautiful medusa, for which we have proposed the name Cnhnia 

 Aphrodite, was found in a surface tow made in the afternoon while we were 

 anchored off Cay Frances, on the northern coast of Cuba, February 17th. A 

 single specimen was captured. The bell was 4.25 mm. wide and 2.7 mm. high, 

 and of a glassy transparency. The velum was distinct and well develojied. 

 The manubrium, radial canals, and edge of the bell were slightly opaque and 

 whitish. Tl:e radial canals were four in number, and the genital organs were 

 situated upon them near the region of the manubrium. They projected .slightly 

 into the cavity of the bell, and were opaque and pearly white in color. The 

 specimen was a male. At the point of exit of each radial canal from the 



