496 



BULLETIN OF THE BUREAU OF FISHERIES. 



men with a dorsal posterior spine; third segment rather abruptly bent downward at posterior end but 

 nut produced into a spine; postero-lateral margin of second abdominal segment with convexity near 

 the middle, below which are several upturned teeth which are continued around the rounded lower 

 angle; postero-lateral margin of third segment of abdomen armed with several prominent upturned 

 teeth; uropods elongated, last pair with the longer ramus nearly three times length of peduncle and 

 armed with live or six spines on the inner and four or live spines on the outer margin; outer ramus 

 about two-thirds length of inner and armed with lour spines on outer margin; telson oblong, entire, 

 and distally rounded. 



Length, 5 nun. Type No. 29242, U. 8. Nat. Mus. 



Described from two rather imperfect specimens taken off Gay Head, Marthas Vineyard. The 

 flagella and last basal joint of first antenme were broken off; first basal joint of these appendage's 

 longer and stouter than second, as in the other species of this genus; second antenme shorter than 

 body; last two joints of peduncle of subequal length and joints of flagellum narrow, sparingly setose 



Ut, 



Apherusa gracilis. Gay Head. The figures on the left represent tin 1 head and the first three segments ol the abdomen. 



and devoid of calceola?; terminal joint of mandibular palp considerably shorter than preceding one 

 and with inner margin slightly concave and miter margin convex. Anterior portion of first three 

 abdominal segments crossed by a light band. Body and appendages with numerous dark pigment 

 cells. Eyes red. 



From Apherusa jurinii and A. borealis this species differs in having the postero-lateral margin of the 

 third abdominal segment armed with numerous teeth. From A. bupinosa it differs in that the carpus 

 and propodus of the first and second gnathopods are much shorter and broader, and in having no 

 large tooth at the upper end of the row of dentations on the postero-lateral margins of the third abdomi- 

 nal segment. It presents the same points of difference from A. megalops, besides having smaller eyes 

 and having the lateral corners of the head rounded instead of produced and acute. It approaches .1. 

 tridentata in the armature of the sides of the abdomen, but differs from that species in having the carpus 

 of both gnathopods very much broader, in having the outer ramus of the terminal uropods relatively 

 shorter, and in not having the posterior margin of the telson serrated. 



Pontogeneia inermis (Kri'iyer). 



Iphimcdia vulgaris Stimpson, Marine Invert. Grand Manan, p. 53, 1853. 



Rostrum narrow, prominent, but not large; antero-lateral angle of head acute; eyes rather large, 

 broadly reniform, fading to a pale color in alcoholic specimens; antennae slender, first somewhat 

 shorter than the second, with first two joints of peduncle of subequal length, the third two-thirds length 

 of second; flagellum slender, over twice length of peduncle; second antenna? over half length of body; 

 last two basal joints subequal; flagellum over twice length of peduncle; flagella of both pairs of 

 antennae furnished with short setee, and on first are small groups of olfactory hairs on alternate joints; 

 first four coxal plates about as deep as their segments, first three deeper than wide and of similar 

 form; gnathopods small, of nearly equal size ami of similar form, the narrow basal joints of each with 

 numerous very short seta 1 on anterior margin and a f -w very long set* posteriorly; carpus of first pair 

 long and narrow, longer than propodus, obliquely truncated at postero-inferior angle, posterior mar- 



