AGASSIZ AND MAYER: ACALEPHS FROM THE FIJI ISLANDS. 171 
There are 8 marginal sense organs, 8 tentacles, and 16 marginal lappets. There 
are 16 broad radial pouches and branched sac-shaped canals within the lap- 
pets. There is no ring canal. ‘There are 4 horseshoe-shaped gonads, the con- 
vex proximal arches of which are divided into two adjacent wings by means of 
a median septum. There are 48-52 (in this species 52) wart-like, hollow pro- 
tuberances upon the floor of the sub-umbrella. 
Specific Characters: Adult Medusa, The bell is 13 mm. high, and 16 mm. 
in diameter. The side walls are straight and vertical, and the top flat. There 
are 16 marginal lappets that are about twice as wide as they are long. There 
are 8 small tentacles that are about 14 times as long as the lappets. Eight 
marginal sense organs alternate with the tentacles. The entoderm of these sense 
organs contains a spherical mass of otoliths (Fig. 34). The 4 gonads are crescent- 
shaped, the two horns of each crescent being separated by means of a median 
partition. There are 16 gastro-vascular pouches, and no marginal ring canal, 
Projecting inward from the floor of the sub-umbrella into the bell cavity there 
are 52 hollow wart-like protuberances. These are arranged in three rows. 
The most proximal row contains 4, the middle row 16, and the most distal 
row 32 of these protuberances. The proboscis is quadrangular in cross section, 
and there are 4 flanging lips. The general color of the Medusa is brown. 
There are 8 rows of dark brown pigment spots running longitudinally down 
the inner surface of the lips of the proboscis. Separated areas of brown ento- 
dermal cells are found in the distal portions of the 16 gastro-vascular pouches, 
Young Medusa. Ephyre of this Medusa were common among the Fiji 
Islands in November and December. They resemble the adult in general color, 
but the umbrella is very flat and disk-shaped. The youngest specimen observed 
by us was 2.5 mm. in diameter. 
We observed the ephyræ of this Medusa off Taviuni, Ngamia, Wailangilala, 
and Vanua Mbalavu Islands, and in Suva Harbor. We also came across a 
large swarm of the adults in the lagoon of Wailangilala Atoll on November 20. 
This Medusa differs from Linerges mercurius, Haeckel, of the West Indies in 
that there are 52 wart-like protuberances upon the sub-umbrella, instead of 48, 
as in the Atlantic species. Also the brown colored entodermal cells approach 
nearer to the stomach, and their color is perhaps slightly duller than in the 
West Indian form. 
Aurelia vitiana, nov. sp. 
Plate 10, Fig. 35. 
Generic Characters. Aurelia, Péron and Lesueur, 1809. Discomeduse with a 
simple central mouth, and 4 mouth arms or palps. The radial canals are nar- 
row and branched, and there is a ring canal. There are 8 marginal sense 
organs, and 8 broad, sometimes bipartite, marginal lappets, each of which 
bears on its dorsal side, some distance away from the umbrella margin, a row 
of numerous short tentacles, that alternate with as many dorsal lappets. 
Specific Characters. The bell is hemispherical and 80 mm. in diameter. 
gelatinous substance is quite thick, 'There are 8 simple marginal lappets 
VOL, XXXII. — NO, 9. 2 
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