Mr. R. V. Chamberlin on new 
~] 
or) 
Number of segments about forty-seven. 
Locality.—Guam Isld. (Owstou Coll.), 1895 (No. 5984). 
Type, Mus. Comp. Zool. (No. 4851). 
Spirostrophus socius, sp. n. 
This species resembles in general appearance and colour- 
markings specimens of J. melanotelus, in which the red 
colour is not developed. The two species were taken 
together on Mt. Makiling in the Philippines. The present 
species may be distinguished easily in lacking the dense 
striation characteristic of melanotelus, 
The body is fulvous to ferruginous below and in a band 
encirling each metazonite, while the prozonites are black, 
the dark annuli disappearing in the light colour ventrally ; 
collum black, narrowly bordered with ferruginous; anal 
segment black, the scutum narrowly bordered behind with 
ferruginous. Legs and antenne fulvous to light brown. 
Antenne short, thickened distad. Eyes somewhat tri- 
angular, with the caudal or upper side strongly convex, the 
mesal and outer sides straight, and the anterior angle 
rounded. Surface smooth ; sulcus widely interrupted in the 
frontal region. Foveole as usual. 
The collum narrowed as usual. Infero-anterior corner 
rouuded, the infero-caudal angle subrectangular. 
Position of sulcus mace clear dorsally by a series of horse- 
shoe-shaped impressions just in front of it ; curved opposite 
the pore. Above the pore level; the surface smooth, ex- 
cepting for the impressions mentioned and a few weak stri 
across the metazonite. Below the pore the metazonite 
crossed by longitudinal striz as usual, with some short 
cuived striz immediately below the pore level just in front 
of the sulvus, but further ventrad these quite absent. Pro- 
zonite often showing numerous fine, short, wavy, mostly 
vertical striz over its anterior part. | 
Anal scutum just equalling the valves. The latter strongly 
margined. 
In the gonopods of the male the median piece has the 
middle or distal plate long and broad, much less trapeziform 
than in S. naresi, the genotype; its distal end also is 
rounded, not truncate, and is mesally slightly notched. ‘The 
proximal arms of the middle piece form a more U-shaped 
figure, with their ends flaring out ectad about the bases of 
the gonopods in the usual way ; the mesal process formed 
by the free part of the outer branch runs directly distad to 
come in contact with the edge of the arch, not diverging 
