ENTOMOSTRACA OF MINNESOTA. 149 
The species of Daphnella found about Minneapolis, occasionally 
abundant, seems not to differ in any important character from Euro- 
pean types of D. brachyura, although I formerly regarded it as distinct 
(D. winchelli, Microscopic Entom., Addenda). 
Head less than one-half the body (about 0.27 mm., while the body 
is 0.6 mm. long); eye about one-fourth head; antenne when reflexed 
extend a little beyond two thirds the length of the body. Male, 0.7 
mm. long; antenne reflexed, reaching base of shell; anterior antenne 
extremely long; copulating organs reaching nearly to end of claws. 
Having carefully compared our specimens with the descriptions and 
figures given by Birge for his D. expinosa, the evidence seems to indi- 
cate not only that they are identical, but both are really D. brachyura, 
The distinctive characters of D. expinosa are a greater indentation be- 
tween head and body, absence of caudal teeth, greater length of male 
appendages, and the opening of the vasa deferentia below the ‘‘instep”’ 
of these appendages. 
The absence of teeth upon the post-abdomen is of even generic im- 
portance according to Sars, who gives it in his synopsis of genera as 
typical for Daphnella. In our specimens the claws are at least pecti- 
nate if not serrate, while the appendages of the male reach generally 
nearly to the middle of the claws. The relative length of these ap- 
pendages and the antenneze of the male is variable. 
Daphnella brandtiana Fischer. 
PLATE XXXVII, Fias. 3-6. 
Head as long as half the body, antenne when reflexed reaching 
beyond the posterior margin of the valves. Length 0.8 mm. Of the 
validity of this species we can form no conclusion. It is usually con- 
sidered a variety or phase of the above. 
Daphnella excisa Sars. 
Sars ’85 (Diaphanosoma excisum). 
Similar to D. brachyura. Head obtusely truncate cephalad, with- 
out distinct sinus beneath the eye, dorsal margin slightly arched. 
Carapace oblong, truncate posteriorly with the dorsal angle nearly a 
right angle, valves inflected in the middle and wide open posteriorly, 
having a well marked angular emargination at the junction of the 
ventral and caudal margins. Eye large. Antenne, when reflexed, 
not reaching the caudal margin of shell. Length 1.30 mm. The head 
occupies about one-third the entire length. The apical claws are 
armed.with three teeth. 
