56 
Labium rather small, reaching, when folded, to the bases 
of the middle legs ; suabmentum shortened; mentum narrowed 
at its proximal end, its median lobe prominent, rounded, fringed 
with a row of flabellate scales whose bases are overlaid and 
supported by another series of shorter semicylindrical scales ; 
beneath this fringe, the margin cut into a series of obscure 
rectangular teeth ; lateral lobes short, nearly straight, unarmed, 
rounded at apex; movable hook stout, moderately incurved, 
and tapering. 
Thorax sloping to the head and to the bases of the legs ; 
prothorax of unusual dimensions on the dorsal side, its hind 
margin on a line with the bases of the hind legs, being extended 
back upon the other thoracic segments, shield shaped, with a 
short collar close behind the head. Wing-cases strongly di- 
vergent. Legs conspicuously fossorial, fore legs approximate 
to the sides of the head, bearing shields of stiff hairs behind 
which the middle legs may be brought forward. Middle legs 
approximated on the venter, rotated downward and extended 
horizontally close under the fore legs. Hind legs longer, more 
nearly normal, directed posteriorly. Fore tarsi with soles fac- 
ing laterally ; middle tarsi rotated on tibiz so as to point back- 
ward ; hind tarsi elongate, the third segment about as long as 
both basal segments, its claws sharp and long; claws of fore 
and middle tarsi short and blunt. Each femur with a distal 
anterior process which rests against and supports the tibia 
when moved backward. 
Abdomen spindle-shaped, segments about equal, the 9th a 
little longer than the others; dorsal hooks variable, rudimen- 
tary, more or less well represented on segments 2 to 9, small- 
est on middle segments. Lateral spines on 5 to 9, on 5 rather 
minute. Appendages slender, tapering; superior and inferiors 
equal, about one third longer than segment 10, laterals about 
half as long as the others. 
