BIGELOW : MEDUSAE FROM THE MALDIVE ISLANDS. 267 



windings of the chyniiferous tul)es are much less complex, and the muscle 

 fibres occupy more nearly the whole substance of the h^es. 



Beroe, sp. 



One young specimen of this genus was taken on January 19, near Guradu 

 island, on the surface. It had arrived at nearly mature form, except that the 

 rows of vibratile combs extended only about halfway from the apical pole to 

 the mouth. The chyniiferous tubes were put into communication by an ex- 

 tremely simple network similar to that described by Agassiz and Mayer for 

 Beroe australis (Bull. Mus. Comp. Zool., vol. 32, p. 177, plate 16). It may 

 be the young of that species. 



Cestus pectenalis, sp. nov. 



Plate 8, Fig. 30. 



A species of Cestus was exceedingly abundant on January 19, on the surface 

 near Guradu i.^land, and on examination proved to be a wholly distinct species. 

 In general form, as well as in its movements, it closely resembles Cestus veneris, 

 but differs from it in the possession of a large and prominent orange spot at 

 either end, and in the extent and structure of the ciliary bands. These extend 

 from near the apical sense organ along the aboral edge of the l)and, following 

 the chyniiferous tube to the extremity of the lobe. They do not extend along 

 the oral edge of the lobe, but come to an end at its extremity. The vibratile 

 combs are comparatively few in number, and set at considerable distances from 

 one another. The cilia are very long and rigid, presenting a comb-like apjiear- 

 ance. The lateral flattening of the animal is excessive. The digestive cavity 

 is liroad, Ijut short. The longest specimen captured measured one metre, by 

 forty nun. in breadth; init the size was very variable. No Cestus with pig- 

 ment patches has ever been described, and the comb-like structure of the 

 ciliary bands, and their restriction to the aboral edge of the animal, are of even 

 greater importance. It seems probable that further investigation may prove 

 them to be of generic significance. Like Cestus veneris, this species is ex- 

 tremely graceful in the water, moving in slow, ribbon-like undulations, and 

 shining with brilliant violet iridescence. 



