Ves *) ae ee a ee ~~) Or aa Ar. ee ee “=, Py we 
ea a af cs, 7 5 wag Dior hice ne oT Ae: Rare 
om : F ho" ho ove | 
f , : r Byes 
202 GEOL. AND NAT. HIST. SURVEY OF MINNESOTA. 
further cephalad, i. e., over the base of the antenne rather immedi- 
ately in front of the heart. The beak in D. dentifera does not turm 
ventrad but caudad. 
* Daphnia dentifera Forbes. 
> PLATE LITT, Fie. 9: 
Forbes 793. 
Broadly oval, long beaked, species with a large eye, posterior 
spine high and with a prominent angle dorsally between heart and 
eye in the male and’ young female. Head broadly rounded, eye near ~ 
front margin. Fornices short, forming a prominent angle behind the 
base of the antenne. Lower margin of head concave, beak projecting. 
Eye large with numerous lenses, its diameter more than half the dis- 
tance from eye to beak. Pigment fleck immediately behind the eye 
and nearer it than the posterior margin of the head. Head crested, 
forming above the insertion of the antenne a rectangular process 
which in the young may bear two or three teeth. This process is re- 
duced to an obtuse angle in the adult female, disappearing in ephip- 
pial individuals entirely. Spine of shell long and slender, one third 
or one-fourth the length of the shell. Caudal ciaws smooth, anal 
spines 13. The two abdominal processes approximate. Length 
of female 1.8 mm. Male 1.0 mm. Very near if not identical with 
D. dentata Matile. This species differs from D. minnehaha chiefly in 
having smooth claws. 
Daphnia longiremis Sars. 
A species of moderate size and very hyaline. Head small and 
rounded, ventral margin somewhat concave, beak sharp, directed 
ventrad. Shell oval, spine short, straight, inclined dorsad. Antenne 
relatively long, extending to caudal margin of shell. Post abdomen 
similar to that of D. longispina. Macula absent. Eye small. Length 
1.0mm. Apparently a pelagic form. We are not certain that ib 
represents an adult. 
* Daphnia magniceps Herrick. 
The peculiar form figured in the tenth annual report of this survey 
seems indubitably new and is distinguished by the peculiar shovel- 
shaped head, which is scarcely crested but is broadest beyond the mid- 
dle. The spine is long, the claws smooth, the abdominal processes 
united and the shell transparent. The eye is near the end of the 
rounded head and is large; the pigmeut fleck was apparently absent. 
Found with Daphnia minnehaha in a shallow swampy pool in autumn. 
