90 



THE MEDUSAE. 



were it not for the facts that in P. triloba the gonads are three-lobed from their 

 first appearance, and that I have not been able to find a gonad with less 

 than three lobes. 



The occurrence of a specimen from the Atlantic shows that Pegantlia triloba is 

 a species of extremely wide distribution. It is of general occurrence through- 

 out the Eastern Tropical Pacific, both north and south of the equator, and has 

 been taken in the Indian Ocean (Zanzibar, Haeckel), and in the Tropical 

 Atlantic, near the island of Ascension (Haeckel, P. quadriloba) and off Rio 

 Janeiro (" Hassler " expedition). It is undoubtedly a surface form, since all 

 the Hawaiian specimens were taken on the surface (Mayer, : 06, p. 1140). 



Pegantha smaragdina, sp. nov. 

 Plate 14, Figs. 1, 2; Plate 19, Figs. 1-9; Plates 22-26. 



Both specimens of this very striking and easily distinguishable species 

 were alive when taken. 



The bell is very low, only about one fifth as high as broad, and in its flat 

 outline much resembles Solmissus, differing correspondingly from other species 

 of Pegantha (PI. 14, fig. 2). The aboral surface is entirely without sculp- 

 ture, and even the otoporpae are so flat that they can hardly be said to form 

 ridges. The lappets are quadrate, about as long as broad ; the incisions 

 between them so shallow that the peroniae are almost as long as the lap- 

 pets (PI. 19, fig. 5). 



Tentacles. — There are thirty-four tentacles and lappets in the larger 

 specimen. Three of the tentacles are much smaller and evidently of more 

 recent growth than the others, but they are already associated with well- 

 developed peronial canals, and bear the same spacial relations to the adjacent 

 gonads as do the larger tentacles. In life, when the animal is idly floating, 

 the tentacles are carried projecting stiffly outward from all sides of the bell, 

 a feature heightening its Solmissus-like appearance. 



Otoci/sts. — There are usually six, sometimes seven or eight otocysts per 

 lappet ; thus in the largest specimen a total of about two hundred. The 

 sense organs themselves are of the usual type, containing from three to five 

 otoliths (PI. 19, figs. 3, 8). They stand on well-marked pads consisting, as 



