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BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



the genital and first abdominal segments. The oviducts have a 

 bluish tinge; the eye is bright red, and behind the eye is a tiny 

 black spot over the base of each first antenna (Rathbun). Wheeler's 

 specimens were full of a dark bluish-black pigment, probably on 

 account of the food they had eaten. 



Feraale. — Metasome flattened; posterior corners of fifth segment 

 expanded unequally, the right side the larger; genital segment 

 asymmetrical, with four stiff spines, two subdorsal, two subventral, 

 the former denticulate; first abdominal segment with a knob on the 



Figure 60. — Centropages typicus: a, Female, dorsal; 6, male, dorsal; c, male, right 

 first antenna; d, male, right fifth leg; e, female, fifth leg. (From W. M. Wheeler) 



right side, none on the left ; second inner caudal seta twice as long as 

 the others. Total length, 1.25-1.75 mm. 



Male. — Body more slender than that of the female ; corners of fifth 

 segment less produced but more asymmetrical, the left one much the 

 larger; urosome symmetrical, 4-segmented; chela of right fifth leg 

 very powerful and overlapping the caudal rami ; the thumb as long 

 as the finger and both rami sharply pointed and curved inward 

 toward each other at the tip. Total length, 1-1.6 mm. 



Reraarhs. — ^Wlieeler recorded this species as nearly always present 

 in the tow taken from the wharf of the Bureau of Fisheries at Woods 

 Hole, and Fish listed it as one of the two most typical summer 



