Meduse 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: 
| L. bartschi. L. bornensis. 
Welanilanpetsecciccct ce cemeen (8X12) all oval and similar each to | (8X7) those adjacent to rhopalar 
| each, lappets being twice as wide as 
the others. 
Interradial papille on the sub- | None.................e.e-eee0: 4, 
umbrella. | 
Perradial niches in the arm-disk.| 4 deep clefts.................... 4 wide, shallow grooves. 
WEOUtN=abmss a oer cee ea, Less than half as long as bell- | About two-thirds as long as bell- 
diameter. diameter. 
PiSmenteseeres ne. eyes tee Numerous. Lateral filaments as | A single slender filament at outer 
| long as those at outer tips of | end of each arm. Other arm- 
|  mouth-arms. Longest filaments filaments are very short and 
are upon arm-disk. | slender. No filaments upon 
| arm-disk. 
Circular muscles): 0.. jess. HDT GED Gos tees ya. 5 Hern ae Shiehoroen ara WE agen interrupted in 8 principal 
| | radu, 
Canalaystem: Sc daccee aed | Network on inner side of ring-canal | Network on inner side of ring-canal 
| does not fuse with the 16 radial- | fuses with 16 radial-canals. 
| canals. 
Central stomach....,..........! Narrow and cruciform............ | Wide and cruciform. 
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). 
Cephea papua, Lesson, 1829, Voyage de la Coquille, Zooph., p. 122, planche 11, figs. 2, 3. 
Mastigias papua, Acassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152.—Mayrer, 1910, Me- 
dusz of the World, vol. 3, p. 678, fig. 415.—Liaut, 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. 
