266 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



ausence of figures of B. microptera leaves me in doubt. The animal is about 

 fifty mm. in length, and in the broad diameter nearly half as wide. In 

 general outline it resembles Bulina vitrea rather than B(jlina septentrionalis 

 Mertens. The lobes are, however, at least one third shorter than in Bolina 

 vitrea, and the digestive cavity is proportionately longer, one third longer than 

 tlie lobes. The auricles are similar in shape to those of Bolina vitrea. The 

 apical sense organ is situated at the bottom of a deep cleft, and is provided with 

 a series of radiating muscle fibres. There are from fifteen to eighteen vibratile 

 combs in each of the short, and thirty to thirty-five in each of the long ciliary 

 bands. Unfortunately in our single specimen the lobes were so damaged that 

 the course of the chymiferous tubes could not be traced with accuracy. 

 Enough, however, remained to show that they were no more complicated than 

 in Bolina vitrea. This is the only point in which it disagrees with A. Agas- 

 siz's description of Bolina microptera. 



Bolina, sp. ? 



On January 19, near Guradu Island, we took a single immature Ctenophore, 

 which is probably a young Bolina. It is in the Pleurobrachia stage, figured 

 by Chun (Mon. Ctenophoren), but the lateral lobes have already begun to ap- 

 pear, and the tentacles are short. The rows of vibratile combs extend nearly 

 to the bases of the lobes. The mouth is a simple slit. 



Ocyroe pteroessa, sp. nov. 



Plate 8, Fig. 39. 



The polar diameter of the animal is about twenty-five mm. The body 

 is so much flattened that the narrow diameter is only one half the broad. 

 The lateral lobes form large wing-like structures, one third longer than the 

 polar diameter. The movements of the animal are effected by their vigorous 

 flappings. The ciliated bands are short, containing but few combs. The auri- 

 cles are short, being only one half as long as the polar diameter, and are always 

 pointed upward. Their edges are lined with a series of stout cilia, set at con- 

 siderable intervals. The digestive cavity is large, variable in form, but is not 

 normally lobed. The windings of the chymiferous tubes are simple, much 

 more so than in Ocyroe crystallina. The " spots " so characteristic of the lobes 

 of Ocyroe maculata are wanting, but most of the substance of the lobes is 

 occupied by stout muscle fibres which radiate to the periphery. 



Ocyroe pteroessa is most closely allied to Ocyroe crystallina Bang, of which 

 Fewkes and Mayer both give good figures (Bull. Mus. Comp. Zool., vol. 9, 

 plate 1, and Bull. Mus. Comp. Zool., vol. 38, plate 31), but diflers from it in 

 several important particulars. The lobes are proportionately larger, the body 

 narrower, the auricles very much shorter, about one half as long. The out- 

 line of the stomach is simple instead of lobed, and it is much shorter. The 



