360 NEMOPSID^E. 



NEMOPSIDvE. 



TROPHOSOME. — Htdeanths with a proximal and distal circlet of filiform 

 tentacles.i 



GONOSOME. — GoNOPHOUES medusiforra planoblasts, with four radiating canals, 

 and with the marajinal tentacles clustered and dissimilar. 



NEMOPSIS, Jffassh. 



Name. — From vjj^iia, a thread, and oy^iQ, cye-siglit; in allusion to the resemblance of the 

 two clavate tentacles in each marginal ckister of the planoblast to the eye-bearing tentacles of a 

 snail. 



TROPHOSOME. — Hydrophtton not known. Htdranth conical ; the proximal 

 circlet of tentacles surrounding the base of the hydranth, the distal one situated at a 

 short distance behind the mouth. 



GONOSOME. — Planoblasts borne by the hydranth between the proximal and 

 distal circlets of tentacles. Medus.e, when mature, deep bell-shaped ; umbrella-walls 

 thick ; radiating canals, terminating each at the margin of the umbrella in a bulb 

 which supports one of the clusters of tentacles ; two of the tentacles in each cluster 

 clavate and but slightly contractile, every tentacle carrying a distinct ocellus at 

 its root ; manubrium with four dichotomously branched oral tentacles ; generative 

 elements produced in four lobes, whose basis of attachment partly rest on the walls of 

 the manubrium, and partly extend for a greater or less distance along the length of 

 the radiating canals. 



The genus Ncmojms was founded by Professor Agassiz" for a medusa captured on the 



' The hydi'ophyton of this family has not yet been discovered. 

 ' ' North American Acaletha;/ part i, p. 289. 



