ENTOMOSTRACA OF MINNESOTA. 103 
mm., stylets 0.14 mm., last two abdominal segments 0.16 mm., antenne 
0.7 mm., first segment of body 0.5mm. The basal segment of the 
antenne is long and ornamented with several transverse series of 
Spines; the last two segments are equal and longer than the preceding. 
The armature of the first and fourth feet is identical with ©. thomasi, 
as is the form of the female openings and the fifth feet. The form of 
the first feet, caudal stylets and other details were correctly figured 
on Plate V of the Cyclopide of Minnesota. 
Specimens of Cyclops pulchellus (thomasi) were obtained from a cistern 
which is supplied solely by rain-water. The eggs must have been in- 
troduced in ice which had been placed in the cistern at least a year 
previously. The cistern is entirely dark, so that these animals must 
have been deprived of light for many generations. The general color 
was, of course, very white; the eye spots were pale, but present with 
some pigment and the lenses. No noticeable alteration in form had 
resulted. / ras 
* Cyclops minnilus Forbes. (|) cr io aA i! 
Forbes ‘93. ah 
A small slender species with 17 jointed antenne, with narrow and 
loosely articulated cephalothorax and salient thoracic angles, slender 
abdomen, long narrow furca, and but two well-developed caudal setz 
for each ramus. The antenne reach to the posterior margin of the 
second distinct segment, and are of very nearly the length of the ab- 
domen (excluding the caudal sete). The greatest width of the thorax 
is contained two and one third times in its length, and the furea is 
very nearly half the length of the remainder of the abdomen. The 
diameter of a ramus is about one seventh its length. 
The rudimentary inner caudal seta is a trifle longer than the outer, 
and about a third the length of the ramus; the longest seta as long as 
abdomen and furea; the next in length less than half the longest. The 
armature of the legs is as follows: 
FIRST FEET. 
ex. 1 seta. ex. 1 seta. 
Outer ramus |p 1spine 2 set. Inner ramus {8 1 spine, 1 seta. 
in. 2 sete. in. 3 sete. 
SECOND FEET. 
ex. 2 spines. ex. 1 seta. 
Outer ramus |p 1 spine, 1 seta. Inner ramus |S 1 spine, 1 seta. 
in. 3 sete. in. 3 Sete. 
THIRD FEET. 
ex. 1 spine. ex. Iiseta. 
Onter ramus {3 *2 spines, 1 seta. Inner ramus {8 1 spine, 1 seta. 
in. 3 sete. in. 3 sete. 
FouRTH FEET. 
ex. 1 spine. ex. 1 seta. 
Outer ramus {se *2 spines, 1 seta. Inner ramus ap. *2 spines. 
in. 3 sete. in. 2 sete. 
* In each case one spine twice as long as the other. 
