34 G. O. SARS. [SEC. ARC. EXP. FRAM 
legs smaller than in female, with the inner expansion of proximal joint 
much shorter and provided with only 3 spiniform sete. 
Length of adult female 1.08 mm. 
Remarks. — The above-described form is unquestionably iden- 
tical with the species recorded by Prof. Litusepore under the above 
name from Siberia. It is about the same size as the type species, 
C. staphylinus (Jurine), which it also resembles in the general form of 
the body, though at once distinguished from it by the very different shape 
of the caudal rami and by the perfectly smooth anal opercle. Like all 
true Canthocampti, it is a genuine fresh-water form. 
Occurrence. — Some specimens of this form occurred in a 
sample taken on June 26, 1899, from some fresh-water pools (the exact 
locality not indicated). 
Distribution. — Northern part of Siberia, at Sopotschaja Korga 
near the mouth of the Jenisei, and on the peninsula Jalmal (LitiseBore). 
117. Ametira longipes, Borck. 
Found rather abundantly in 6 different bottles. 
118. Ameira tau (GIESBRECHT). 
Some few specimen of this small species occurred together with the 
preceding form in one of the bottles. 
119. Parameira elongata, G. O. Sars, n. sp. 
(PI. X). 
Specific Characters. — Female. Body very slender and 
elongated, sub-cylindric in form, with the anterior division scarcely 
broader than the posterior. Cephalic segment about the length of the 
3 succeeding segments combined; rostral projection almost obsolete. 
Urosome fully as long as the anterior division, and having the segments 
apparently perfectly smooth; last segment larger than the preceding one, 
and deeply incised behind. Caudal rami rather far apart and somewhat 
produced, being almost twice as long as they are broad; middle apical 
setee rather slender and elongated. Anterior antenne of moderate length 
and densely clothed with slender sete, 8-articulate, terminal part exceed- 
ing half the length of the proximal one, and having the penultimate 
joint imperfectly divided in the middle. Posterior antenne and oral 
parts exhibiting the structure characteristic of the genus. 1st pair of 
legs with the rami very unequal, the outer one extending to about the 
