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192 GEOL, AND NAT. HIST. SURVEY OF MINNESOTA. | 
abdomen not ciliate, of moderate size. Anal teeth 10, nearly equal. 
Claws bipectinate. Abdominal processes discrete. Length 1.08 mm. 
It still seems probable that this is an age form of some species with 
longer spine. 
Daphnia alpina Daday. 
Daday ’88. 
Head short, somewhat produced ventrad, front rounded, ventral 
margin almost straight; beak rather acute, short, extending ventrad. 
Eye large, rather remote from the margin of the head. No crest. 
Shell almost round, ventral margin obviously rounded; spine absent 
or very short, simply forming an acute angle. Post-abdomen small, 
laterally setose, bearing 11 to 12 anal spines which are short and 
curved and slightly diminish in size dorsad. Claw with a comb of 
long teeth and a continuous series of fine spinules. Abdominal pro- 
cesses discrete. Length 1.2 to 1.9 mm., depth 0.9 to 1.15 mm. 
The resemblance to D. obtusa Kurz is very close, but that species 
has the sides of the post-abdomen smooth, the ventral margin of the 
head concave and the spine near the middle of the caudal margin of 
_ the shell. The shell is longer and more oval in outline. Weshould | 
wish to be very sure that these are not both old individuals of a spe. 
cies having the usual spine in younger stages. 
Daphnia hastata Sars. 
A large species of reddish color, with strongly depressed head, 
whose ventral margin is convex. Shell oval, with along spine. The 
abdominal processes are long and approximate. Anal spines Ilo. 
Length 3.0 mm. This species was inadequately described by Sars 
and probably should be dropped. 
Daphnia ornata Daday. 
Daday ’84! (serrulata); ’88. 
Head not separated by a depression from the thorax. Beak rather 
acute, short, turned ventrad. Eye distant from the margin of the 
head. Shell oval, margins rounded, with a moderate spine directed 
caudad. Post-abdomen scarcely attenuated apically with eight to ten 
curved anal spines, diminishing dorsad; sides setose. Claw with a 
basal series of spines and a continuous series of fine sete. Abdominal 
processes discrete, ciliate. Length 1.0 to 1.5 mm., height 0.85 to 1.0 
mm. The ventral margin of the head in this species is more curved 
than in D. alpina, and this might well be a younger form of D. obtusa, 
though the sete on the sides of the abdomen are not noted in that 
spectes. 
