226 



BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



four spines and two setae; distal segment of fifth legs oval and 

 rather pointed, with five setae, the middle (terminal) one filiform, 

 basal expansion nearly reaching the center of the distal segment, Avitii 

 five plumose setae, the middle one the longest. Total length, 

 1-1.2 mm. 



Male. — The first antennae are geniculate, the fourth segment con- 

 siderably swollen and bearing a very long aesthetask ; second basipod 

 of first legs Avith a small knob on the inner margin, and at the distal 



corner a laminate process squarely 

 truncated at its tip; and inside of this 

 a short, stout spine; distal segment 

 of second endopod with a small knob 

 on its inner margin and a stout bay- 

 onet-shaped apical spine, the base of 

 which is swollen into an inner knob; 

 inside of this apical spine and parallel 

 with it is a second spine of equal length 

 but more slender. Distal segment of 

 fifth legs as wide as long, with five 

 setae, the two inner ones plumose and 

 widely separated, the middle one ter- 

 minal and filiform, the two outer ones 

 short and spinelike; inner expansion 

 very short, with 2 or 3 unequal setae 

 and numerous spinules. Total length, 

 0.75-1 mm. 



Remarks. — The characters most easily observed are the caudal 

 rami, longer than wide, and the outer apical seta swollen at its base. 

 The distal segment of the fifth legs in both sexes has but five setae, 

 the middle one alone apical and filiform. The species has not before 

 been reported from our coasts. 



AMPHIASCUS INTERMEDIUS (T. Scott) 



Figure 152 



StenJielia intermedia T. Scott, IStli Ann. Rep. Fishery Board Scotland, pt. 3, p. 



169, pi. 2, figs. 10-21, 1897. 

 Amphiascus intermedlus Saks, Crustacea of Norway, vol. 5, p. 169, pi. 110, 1906. 



Occurrence. — Nine females were obtained from Quisset Pond, 

 Falmouth, July, 1926. 



Distribution. — Scottish seas (T. Scott); Norwegian coast (Sars). 



Color. — Body a uniform yellowish gray and fairly transparent; 

 eggs white and opaque ; eye bright red. 



Female. — Body short and stout, not more than three times as long 

 as wide; cephalic segment broad and evenly rounded anteriorly; 

 rostrum bifid at its tip ; urosome one- fourth shorter than metasome ; 



Figure 151. — Amphiascus Jiispidus: 

 a, Male, second leg ; b, female, 

 fifth leg ; c, male, fifth and sixth 

 legs 



