NO. 4 TWO NEW CKINOJDS CLARK 3 



and sixth are five or six times as long as the median width ; those 

 following decrease in length so that the last 12 are only about one 

 third again as long as broad. The elongate earlier segments have 

 expanded ends, the distal end being somewhat produced, especially 

 dorsally, and slightly overlapping the base of the segments following. 

 On the short and more compressed distal segments the production of 

 the distal edge dorsally becomes narro\ve(l and accentuated so that the 

 dorsal profile of the outer portion of the cirri is strongly serrate, 

 whereas the ventral profile is smooth. The opposing spine is triangu- 

 lar, erect, arising from the entire dorsal surface of the penultimate 

 segment, equal to half the width of the segment in height, and much 

 higher than the production of the distal edge of the segments pre- 

 ceding. Tl)e terminal claw is small, conical, and scarcely curxcd. 



Pi is 4.4 mm long with 17 segments and is slender and eveiilv 

 tapering. The first three segments are about as long as broad, and 

 those following slowly increase in length so that the seventh is about 

 twice, as long as broad, the tenth is about three times as long as the 

 median width, and the outermost are about four times as long as 

 the median width. From the tenth onward the segments are constricted 

 centrally, and the slightly projecting distal edge is finely spinous 

 dorsally. 



Po is 4.3 mm long with 1 2 segments, of which the first is about 

 as long as liroad, the second is al)out one third again as long as 

 broad, the third is somewhat UKjrc than twice as long as broad, and 

 those following are greatly elongated with slightly produced and very 

 finely spinous distal ends. The pinnule is about as stout basally as 

 Pi but tapers rather more rapidly, the distal half lieing very slender, 

 though not flagellate. 



P3 resembles Po and is about the same length or slightly shorter, 

 with about 10 segments. It is about as stout basally as P2 but tapers 

 more gradually and evenly, so that it appears stouter in the proximal 

 half. It bears a gonad which extends from the middle of the fourth 

 to the end of the proximal third of the sixth segment. 



The next three pinnules are similar to P.-,. 



The distal jiinnules are 6.0 mm long with 17 segments, which, 

 except for the first two, are much elongated and very slender. 



Remarks. — No species of the genus Psathyrometra has heretofore 

 been known from the Atlantic. It is represented in the Indian and 

 Pacific Oceans by 14 species, which range from the eastern coast of 

 India to the Lesser Sunda, Philippine, and Hawaiian Islands, thence 

 northward to the northern part of the Sea of Japan and the Aleutian 



