34 PROCEEDINGS OF THE NATIONAL MUSEUM vol.80 



segment, a little longer than wide, with a transverse dorsal suture 

 nearly at the center. The two basal segments of the abdomen nearly 

 the same length and width, the terminal segment about as wide as 

 the others but much shorter. Caudal rami tapered so that the tips 

 are about half the width of the bases. Of the four terminal setae 

 on each ramus the two outside ones are short, the two between them 

 longer, the inner of these two twice as long as the outer. Both the 

 upper and the under surfaces of these rami are covered with short 

 hairs. 



The first antennae are stout, 5-segmented, and armed with coarsely 

 plumose setae. The exopod of the second antennae is as long as the 

 endopod and 7-segmented, and both rami are armed with stout 

 setae. The chewing blade of the mandible is stout and widened con- 

 siderably at the tip, which is armed with five coarse and rather blunt 

 teeth on the inner side, and a bunch of four or five slender and very 

 sharp ones at the outer corner. Maxillae and maxilliped similar to 

 those in other species of the genus, with minor differences. 



First legs shorter than the other pairs ; spines on the exopod long, 

 stout, and pectinate; endopod much longer than the exopod but 

 not so wide; spine just inside the base of the endopod nearly as long 

 as the two basal joints of the latter and smooth. Fourth legs slender, 

 the endopod much longer than the exopod, with small and com- 

 paratively weak spines at the inner distal corners of the first two 

 joints; no spine on the outer margin of the terminal joint of the 

 exopod and no seta on the inner margin of the second joint. Fifth 

 leg a minute lamina, tipped with four tiny setae. Egg sacs large 

 and elongate-oval in form. 



Color (preserved material). — A light brownish yellow. 



Measurements. — Total length, including furcal rami, 1.65 mm.; 

 width of head, 0.3 mm. 



Occurrence. — Seven females, two of which carried egg sacs, were 

 obtained in the bottom net at Station W on June 3, 1921, drawn 

 from a depth of 13 meters over a muddy bottom. The male is un- 

 known. 



Types.— \].^:^M. No. 58571, holotype ; No. 63417, paratypes. 



Remarks. — T. Scott established this genus for a species obtained 

 in the Firth of Forth. G. O. Sars found the same species on the 

 Norwegian coast and also a new species in the upper part of Chris- 

 tiania Fiord. The present species differs from these two in the 

 length of the abdomen, in the width and bluntness of the rostral 

 plate, and in the details of the mandibles and the first and fourth 

 swimming legs. Like the other species it was found in shallow 

 water over a muddy bottom. It does not occur in sufficient abun- 

 dance to render it of any economic importance in the life of the bay. 



