694 



MEDUS.E OF THK WORLD. 



GENERIC CHARACTERS. 



Rhizostomata lorifera in wlilcli the 8 mouth-arms bear rows of three continuous frilled 

 mouths, but terminate each in a naked knob. 



Among characters of minor importance the suhgenital ostia are usually wider than the 

 perradiai disk-columns. The circular muscles of the suhumhrella are practically entire. The 

 sense-clubs have each an ocellus and a well-developed, exumbrella pit with radiating furrows. 



All the species are from the Indo-PaciHc region. 



Tabular Description of the Species of Lorifera. 



Lorifera lorifera HaeckeL 



Rhizostoma lorifera, Ehrenbcrg, 1835, Abhandl. Berlin. .Acad., p. 260. 

 Lfptobrachia lorifera, .AciASSIz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 154. 

 Himantoitoma lorifera, Haeckel, 1880, Syst. der Medusen, p. 628, laf. 38, fign. 1-6. 

 ( .^) Himantoitoma sueurii, A(iASSI2, loccit. p. 152. 

 Lorifera arabica, Haeckel, loc. cit., p. 628. 



Bell 150 to 160 mm. wide with very thin walls and smooth e.xumbrella surface. 8 rhopalia. 

 64 marginal lappets. In each octant 6 short, wide, bluntly-rounded, double, velar lappets 

 between 2 rudimentary, oval, ocular lappets. The 4-sided arm-disk is somewhat wider than 

 the bell-radius. The 4 suhgenital ostia are 3 to 4 times as wide as the perradiai columns 

 between them. There is a narrow, cruciform, suhgenital cavity. The 8 long, tapering, whip- 

 like mouth-arms are twice as long as the bell-diameter. Near the arm-disk they are only 5 to 

 6 mm. wide and taper outwardly, being only 2 to 3 mm. at their ends where they terminate 

 in a naked, oval knob 5 to 6 mm. long. A ventral and dorsal row of complexly folded, frilled 

 mouths is found in the upper half of each mouih-arm, and thus the upper half of the arm is 

 triangular in cross-section, with a double row of mouth-frills at each of the 3 angles. The 

 ventral (inner) ridge of mouths disappears about the middle of each arm, the lower halves of 

 the arms being thus ribbon-like with onl\- the 2 lateral rows of mouth-frills persisting to the 

 base of the terminal knob. Neither clubs nor filaments between the mouths. There is a wide 

 unitar\' zone of circular muscles in the subumbrella and apparenih' no radiating muscle-fibers. 



Stomach cruciform, the 4 perradiai oral rays of the cross being 60 mm. long and twice as 

 wide (30 mm.) in their outer half as they are near the center of the bell. 8 rhopalar radial- 

 canals arise from the stomach and extend to the marginal sense-organs. These 8 canals are 

 put into connection one with another by a ring-canal at some distance inward from the margin. 

 On its outer side the ring-canal gives off a network of vessels which fuse with the rhopalar 

 canals, and on its inner side there is a wider-meshed network of vessels which fuse with the 

 radial-canals and with the central stomach. There are traces of 8 narrow, adradial canals in 

 the network. 



The bell is amethyst-color with a w'hite margin and with a dark-violet spot upon each 

 lappet. The frills of the mouths are dark-violet and the gonads reddish-yellow. 



Found at Tur, near Saini, Red Sea, in November. 



This medusa may be identical with Agassiz's "Himantostoiiui sueurii" from the China 

 Sea; but in this form there are only 5 velar lappets in each octant instead of 6 as in L. lorifera. 



