138 GEOL. AND NAT. HIST. SURVEY OF MINNESOTA. 
nine times as long as the stylet. The fifth foot of the female nearly 
as in the previous species, but the proportions of the sete differ. The 
fifth feet of the male are like those of M. albuquerquensis. The antennee 
of the male seem to be different. In WM. albuquerquensis the apical seg- 
ment is larger and the flagellum is long and of uniform width, while 
in the present species the flagellum is short and clavate. The swim- 
ming feet seem similar. Length of male 0.56 mm., length of first seg- 
ment 0.15 mm., length of stylet 0.04 mm., length of longest seta 0.28 
mm. to 0.54 mm. 
The stylets in the female of I. albuquerquensis measure 0.072 mm. 
in the female and over 0.08 in the male, the longest seta being 0.37 
and 0.42 respectively. 
It must remain for larger experience to determine the value of 
these distinctions, which rest on comparatively few individuals in the 
case of MW. brevicaudata. . 
- ak p= a 
ee eee - 
