MARINE ISOPODS FROM THE PHILIPPINE ISLANDS. 



11 



Fig. 9.—Argathona 

 sulcata. X 2£. 



The first and fourth segments of the thorax are subequal, each being 2 mm. long; 

 the second, third, fifth, and sixth are subequal, each being 1.5 mm. in length; the 

 seventh segment is slightly shorter than the sixth. All the 

 segments except the first are provided with epimera, those of 

 the second and third segments being rounded posteriorly and 

 not extending beyond the postlateral angles of the segments; 

 those of the last four segments become gradually more acute 

 and more produced beyond the postlateral angles of the seg- 

 ments, the epimera of the seventh segment reaching the post- 

 lateral angles of the third abdominal segment. 



The first segment of the abdomen is entirely concealed by the 

 last thoracic segment ; the three following segments are short and 

 subequal; the fifth is a little longer than any of the preceding 

 segments. The sixth or terminal segment is nearly as long as 

 wide, 5 mm.: 5.5 mm., is triangular in shape, with apex acute. 

 On the dorsal surface are four longitudinal carinate ridges, one 

 on either side of the median line and one on either side along 

 the lateral margin. Between these carinas are three grooves 

 or sulcate regions. The inner branches 

 of the uropoda do not extend beyond 

 the extremity of the abdomen; they 



have the outer posterior angle roundly produced . The outer 

 branch is slightly shorter than the inner branch and is ovate. 

 The margins of the uropods are coarsely crenulate; those of 

 the terminal abdominal segment are minutely crenulate; 

 all are furnished with hairs. 



The first three pairs of legs are prehensile; the last four 

 pairs ambulatory. 



Only one specimen was collected, at station 5453, east 

 coast of Luzon, Legaspi Light, at a depth of 146 fathoms. 

 Type specimen, catalogue number 41010, United States 

 National Museum. 



Argathona similis, sp. nov. 



This species is close to Argathona setosa, but differs in its 

 larger size, being 7 mm. : 19 mm. ; in its longer antennae, those 

 of the first pair extending to the end of the fourth peduncular 

 article of the second pair and those of the second pair ex- 

 tending to the end of the third abdominal segment on one 

 side and to the end of the sixth thoracic segment on the 

 other; in having the terminal abdominal segment more acute 

 and tipped with four seta?; in the differently shaped inner branch of the uropoda; 

 and in the wider space between the eyes. 



One specimen, a male, was collected at Limbe Strait, Celebes. Type, catalogue 

 number 41015, United States National Museum. 



Fig. 10.— Argathona 

 similis. X 3. 



Family ^GIDy93. 

 Genus ZEGA Leach. 



2Ega excisa, sp. nov. 



Body oblong-ovate, 13 mm. wide and 36 mm. long. Color, in alcohol, yellow. 

 Surface punctate. 



Head wider than long, 3 mm.: 7.5 mm., with the anterior margin produced in a small 

 median point. Eyes large, oval, meeting in the center of the head and occupying 

 most of the dorsal surface. There is a small V-shaped space in front of the eyes, and 



