382 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Gonionemus vertens A. Ag. Fig. 103. 
(Cont. Nat. Hist. U. S., iv, p. 350.) 
Bell hemispherical. Marginal tentacles numerous, each with a sense-bulb at its base and a 
“knee-pad” of adhesive cells near its end, which appears as a thickening of the tentacle. Otocysts 
numerous bet ween the bases of the tentacles. Proboscis short, not reaching more than half way to the 
velum, and ending in four frilled mouth-arms. Radial canals, 4. Ovaries 4, forming convoluted bands 
following the radial canals to the bell margin. 
Colors . — Tentacle bases emerald green and brown, with a black eye-spot. Proboscis and ovaries 
yellowish brown. 
Distribution . — The Eel Pond, at Woods Hole. 
Melicertum campanula Esch. Fig. 104. 
(Syst. der Acal., p. 105.) 
Bell deep, the upper portion somewhat narrowed. Marginal tentacles numerous, hollow, with- 
out eye-spots at t heir liases. No otocysts. Proboscis short, ending in eight frilled mouth-arms. Radial 
canals 8. Ovaries 8, convoluted, extending beneath the radial canals to the margin. 
Colors. — Ovaries, proboscis, and tentacle bases light yellow. 
Distribution . — Woods Hole. (Vinal Edwards.) 
102. Trachynema digitals, 
( Fabr. ) . 
103. Gonionemus vertens A. Ag. 
104. Melicertum campanula Esch. 
-iEquorea albida A. Ag. 
(North American Acaleplue, p. 110.) 
Bell rather shallow, in the shape of a low dome with lateral outlines slightly sinuous. Marginal 
tentacles very numerous, with otocysts between their bases and without evident sense-bulbs. Pro- 
boscis small, but evident, without mouth-arms. Radial canals very numerous. 
Colors . — Radial canals appearing as whitish lines. 
Distribution . — Buzzards Bay; Naushon. (A. Agassiz. ) 
I have not seen this species, and the above description is taken from that of the original describe!-. 1 
Zygodactyla groenlandica Ag. 
(Cont. Nat. Hist. U. S., vol. iv, p. 360.) 
Bell shallow, a low dome, hardly emarginate along the lateral outlines. Marginal tentacles 
exceedingly numerous, swollen at their bases. Otocysts numerous; situated between the tentacle 
bases. Proboscis large, thin-walled, reaching beyond the bell opening when not retracted, and sur- 
1 Since the above was written numerous specimens of this species have been secured at Woods Hole by Mr. Hal. Childs. 
