MNEMIOPSIS. 



19 



Bolina vitrea Agass. 



BoUna rilren AoAss. Contrib. Nat. Hist. U. S., Vol. III. pp. 2fi!), 289, Fig. 9.3. 18G0. 

 f Bolina lillorali.t McCr. On the Development of two Speeies of Ctenophors, 1857 ; IVoc. Elliot 

 Soc.X. H., p. 1. 1858. 



The Bolina lifforaUs McCr. i.s proljahly either this 

 speeies, or one of our species of Mnemiopsis ; l)ut 

 uot having the means to determine this point, a 

 figure (Fig. 19) of the Bolina vitrea Agass. is added 

 here, to serve as a basis for its identification here- 

 after. 



Reef of Florida (Agassiz) ; Charleston (McCradj). 



Fig. 19. 



Bolina raicroptera A. Agass. 



Bolina srplenlrionalis Agas.s. (non Mertens). Cont. Nat. Hist. U. S., III. p. 289. 18G0. 



The discovery of several species of Bolinida3 on the eastern coast of 

 North America, belonging to different genera, which had all been con- 

 founded together, has induced me to examine anew the descriptions 

 and drawings of the species of Bolina observed on the northwest coast. 

 I have become satisfied that the species of Bolina here noticed is not 

 the B. septentrionalis of Mertens, but diftei's specifically from it. It 

 is quite elongated ; the lateral lobes are very short, with complicated 

 windings of the long ambulacra! tubes. This species resembles m out- 

 Ime more the BoUna vitrea Agass. than any other. It has, like it, 

 a long digestive cavity, but differs from it in the proportions of the 

 lateral lobes, and the complexity of the windings of the long ambulacra. 

 It is, like the B. vitrea, perfectly transparent and nearly colorless, of a 

 slight bluish tinge ; the polar diameter measures about two inches. 

 Found in June, in the Straits of Rosario, Washington Territory. 



Guh" of Georgia, W. T. (A. Agassiz). 



MNEMIOPSIS Agass. 



Mnemiopsis Agass. Cont. Nat. Hist. U. S., HI. pp. 2fi9, 290. ISGO. 



The genus Mnemiopsis is remarkable among the Bolinidiu for the 

 peculiar structure of the tentacular apparatus, which sends a branch 

 along a deep furi'ow, protected by a lappet, to the base of the auricles. 



Fif;. 19. Bolina vitrea si'en from tlie broad siile. /",/', lon<; anibulaera ; /',/', short anilm- 

 laera ; /, fminel ; it, dijiestive cavity ; /, tentacular tube ; ;^', ;^', auricles ; /, /, anterior ami poste- 

 rior lobes ; W, tentacle. 



