672 



MEDUS/E OF THK WORLD. 



There are 8 separate mouth-arms, each three-eighths as long as the bell-diameter. The 

 lower, 3-winged, expanded part of each arm is about 5 times as long as the simple, flattened, 

 upper part of the arm. Each mouth-arm is bluntly pointed and us frilled mouths lack fila- 

 ments or other appendages. The mouth-frills extend to the extreme tip of the arm and there 

 is no naked, terminal portion. 



A zone of powerfully developed, unbroken, circular, subumbrella muscles extends from 

 the outer edge of the arm-disk to the bell-margin. The gelatinous substance of the bell is 

 very tough and of a leathery consistency. 



16 radial-canals leave the central stomach: 8 rhopalar and 8 adradial. These are con- 

 nected by a ring-canal on the outer side of which there is a fine-meshed and on the inner side 

 a coarse-meshed network of anastomosing vessels. 



The medusa is dull, uniform dark brownish-purple, resembling old leather soaked in 

 water. It is abundant in Manila Bay, Philippine Islands, where it occurs over the bottom 

 in shallow water. 



Seven specimens found in Manila Bay on December 9, 1907, are in the collection made 

 by the U. S. Fisheries Bureau steamer Albatross, and a larger one on March II, 1908. This 

 largest specimen serves as the type of the species in the National Museum at Washington. Its 

 dimensions in mm. are as follows: Bell 1 15 wide, evenly rounded, 35 high; arm-disk 75 wide 

 where it arises from the subumbrella, 52 wide at level of origin of mouth-arms; mouth-arms 

 58 long, upper arm / long, lower arm 51 long and 30 wide. 



FIG. 412. Catost\lus purpurus, sp. nov. Drawn by the author, from specimens obtained by the U. S. Bureau of 



Fisheries steamer Albatross in Manila Harbor. 

 A, oral view, half natural size. Only two of the mouth-arms are shown; $ others are cut off close to their points 



of origin, and one is shown cut across in its expanded 3-winged part. B, side view. C, genital ostiuin 



showing subumbrella papilla flanked by a pair of cocks-comb-shaped subumbrella projections. D, 



exumbrella view of rhopalium showing furrowed sensory pit. 



Genus LYCHNORHIZA Haeckel, 1880. 



7,v lin(jrlii?a+ Cramborhiza, HAECKEL, 1 880, Syst. der Medusen, pp. 587, 633. VANHOFFEN, 1888, Bibliotheca Zoologtca, Bd. I , 



Heft. 3, pp. 28, 41 . 

 Lycl:norhisa,MfLAS, 1903, Scyphomedusen der Siboga Exped., Monog. 1 1, pp. 48, 80; 1906, Revue Suisse de Zool., tome 14, p. 102. 



The type species is Lychnorhiza lucerna Haeckel, from the coast of Brazil, Rio de Janeiro 

 to Pernambuco. 



GENERIC CHARACTERS. 



Rhizostomata triptera with filaments, but without clubs, upon the 3-winged mouth-arms. 

 No axial terminal club at the end of each arm, and no club-shaped appendages between the 

 mouths. The stomach gives rise to 16 radial-canals : 8 rhopalar and 8 adradial. The rhopalar 

 canals extend to the bell-margin, but the adradial ones end in the ring-canal. Blindly ending 

 centripetal vessels arise from the inner side of the ring-canal and may anastomose to some 

 extent. On its outer side the ring-canal gives off a network of anastomosing vessels which 

 extend into the lappets. 



