96 CARL BOVALLIUS, THE OXYCEPHALIDS. 



The telson is more than two and a half times as long as it 

 is broad at the base; arid is considerably longer than the 

 last pair of uropoda; the apex is broadly rounded. 



The helmet-shaped head (PL IV, fig. 7) viewed in profile resembles 

 that figured by STREETS (26, pi. 2, fig. 36) from the female of St ebbing ella 

 ftclerotica. It is very broad and deep, almost as deep as it is long 

 without the rostrum. The under side of the rostrum is bordered behind 

 by a small duplicature of the integument. 



The first pair of antennae (PL IV, fig. 8) have the first joint of 

 the flagellum twice as long as it is broad at the apex; the three following 

 joints are subequal in length, and are together quite as long as the under 

 margin of the first joint. 



The perceon has the segments very neatly defined but not pro- 

 truding. The epimerals are entirely smooth and even, without tubercles 

 or spinous processes, and are somewhat longer than the under margins 

 of the corresponding personal segments. 



The first pair of perceopoda (p. 32, fig. 53) have the carpus 

 nearly as long as broad; the metacarpus is as long as the carpus, with 

 the front margin convex; the dactylus is gently curved, half as long 

 as the metacarpus, arid smooth on the hind margin. The second pair 

 (PL IV, fig. 9) are only a little longer than the first; the metacarpus 

 is a little longer than the carpus; the dactylus is half as long as the 

 metacarpus, and is like that in the first pair. The third and fourth 

 pairs are very slender and equal in length. The fifth pair are longer 

 than the sixth ; the femur is broad, only a fourth part longer than broad, 

 and a little longer than the three following joints together. The femur 

 of the sixth pair is broadly pear-shaped, about a fifth part longer 

 than broad, and about a sixth part broader than that of the fifth pair. The 

 seventh pair have an almost trapeziform femur, which is as broad at the 

 base as it is long, and a little longer than all the following joints together. 



The pleon is somewhat longer than the last five peraeonal seg- 

 ments together. The under margins of the segments are straight. 



The last coalesced ural segment is less than a third part longer 

 than it is broad at the base. 



The first pair of uropoda (p. 38, fig. 72) reach a little beyond 

 the middle of the inner ramus of the last pair; the peduncle is 

 longer than the last coalesced ural segment, almost linear, and about 

 four times as long as broad, with the lower parts of the margins 



