Medusce of the Philippines and of Torres Straits. 



193 



canals. On its outer side the ring-canal gives rise to about 100 radiating 

 vessels all of which anastomose by side branches, forming a reticulum in the 

 outer zone of the subumbrella. 



In formalin the gelatinous substance is translucent and milky and the gonads 

 and mouth-frills are milky yellow. 



The following table will serve to indicate the distinctions between Lych- 

 norhiza bornensis and Lychnorhiza bartschi of the Philippines: 



Genus MASTIGIAS L. Agassiz, 1862. 



Mastigias, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152. 



GENERIC CHARACTERS. 



Rhizostomata triptera with 3-winged mouth-arms, which terminate in a 

 naked, club-shaped extremity. There are also smaller clubs and filaments 

 between the frilled mouths. The mouths are developed not only along the 

 edges of the 3 leaf-like wings of the lower parts of the mouth-arms, but also 

 over parts of their flat, expanded sides. The central stomach gives rise to 

 8 rhopalar-canals and numerous, interocular radial-canals, all of which anas- 

 tomose and finally connect with the ring-canal. The rhopalar-canals extend 

 straight to the sense-clubs, but the inter-rhopalar-canals end in the ring-canal. 

 On its outer side the ring-canal gives off a network of vessels which extend 

 into the lappet-zone and fuse with the outer ends of the rhopalar-canals. The 

 ring-muscles of the subumbrella are interrupted in the 8 rhopalar radii. There 

 is a unitary subgenital porticus. 



Mastigias papua (Lesson). 



f'ephea papua, LESSON, 1829, Voyage de la CoquiUe, Zooph., p. 122, planche 11, figs. 2, 3. 

 Mastigias papua, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152. MAYER, 1910, Me- 



dusEe of the World, vol. 3, p. 678, fig. 415. LIGHT, 1914, Philippine Journ. of Science, vol. 



9, p. 209. 



This common medusa is widely distributed over the Malay Archipelago, 

 Indian Ocean, and China Sea to Japan, and outward over the Pacific to the 

 Fiji Islands. It gives rise to a number of varieties. Eight specimens, the 

 largest 59 mm. in diameter, were found by the Albatross in the Philippines. 

 Two specimens are from Santiago River, Pagapas Bay, Luzon, February 20, 

 1909; two are from Pandanon Island between Cebu and Bohol, March 24, 

 1909, and four were taken on the surface off Cebu on September 5, 1909. It 

 was abundant in shallow water among the mangroves in Port Moresby, Papua, 

 in November 1913. 



