
480 THE AMERICAN NATURALIST. 
Ventral plates with a single median sulcus which caudad becomes indis- 
tinct or obsolete, with a transverse furrow or depression; excepting the 
first few, with a rather large median poriferous area on the anterior por- 
tion of plate, this often, especially caudad, prolonged backwards in the 
form of a narrow tongue; ventral pores also arranged on each side of the 
sulcus in front of the posterior border. 
Anterior spiracle intermediate in size, those succeeding very gradually 
decreasing, caudad becoming small. 
Legs pilose with mostly rather long hairs; first pair distinctly reduced, 
the second pair intermediate; anterior and posterior pairs not much differing 
in size; anal legs of male strongly swollen, densely clothed with short to 
very short fine hairs, longer than the penultimate, anal legs of female not 
at all swollen, similarly pilose to other legs, armed with a short pale claw. 
Pleurz of last segment with 7-11 small obliquely seriate pores on each 
side; last ventral plate wide, sides curved, strongly converging posteriorly, 
anterior border produced forwards from sides to middle line, making the 
mee: tocan: anal pores present. 
rs of legs of male 43-47, of female 47. Length of average male 
21 mm., width 1 mm. ; length of female 20 mm., width 1.2 mm. 
Adolescens. — Specimens 12.5—13.5 mm. long measure .4—6 mm. in 
width; length of antenne .6-.7 mm.; pleural pores 4-6 on each side ; 
color yellowish or light brown. 
Fetus.— One individual examined is still coiled up within the egg, the 
yellowish outer membrane, or shell, of which, however, is evenly split down 
one side from end to end, the thin transparent inner membrane being still 
intact; in this condition the egg is spherical and measures 1 mm. in 
diameter. 
An individual 4 mm. long is free excepting posterior segments, these 
still covered by the membranes; legs short and rather stumpy, closely 
crowded ; antennz bent back under the head along the not yet fully 
ed mouth parts. 
pecimens 4.5-7.5 mm. in length still spirally coiled; width .4 mm. 
and under ; antennae extended, as usual relatively long, clavate, joints very 
short excepting the ultimate, the sy as long as the three or four pre- 
ceding taken together ; color brow 
Habitat.— In the quaking aspen ugar pine woods along the head waters 
of Manti and Pole canyons, San Pete County, and about the glacial lakes 
at the head of Little Cottonwood canyon, Salt Lake County. 
All the specimens of the fetus stage, ten in number, were found together 
with the body of the — coiled about them, the nest being a pit in the 
underside of a log. 
The types were cni in Pole canyon, July 15, 1901. 
LATTER-DAY Saints’ COLLEGE, SALT LAKE CITY, 
December 17, 1901. 
