No. 416.) NORTH-AMERICAN INVERTEBRATES. 671 
bodies are a serviceable protection. When handled they often 
. exude a whitish fluid, which in some species has a disagreeable 
odor. 
The points for the separation of species are often best 
observed in the males; this is especially true in the large 
genus Liobunum, in which the females are not known for 
several species. The males, as a rule, have more slender legs 
and palpi, and a more tapering abdomen ; but in some species 
the abdomen of the male is very short and broadly truncate. 
In Liobunum the last joint of the male palpus shows a row of 
small denticles beneath. In a few forms the male has the 
hind coxa enlarged. In several cases there are colorational 
differences between the sexes. In many forms the male is 
more spinose than the female. The order Phalangida is 
usually divided into two suborders: Mecostethi (Laniatores 
of Koch) and Plagiostethi (Palpatores of Koch): 
First ventral segment of abdomen not reaching in front of hind coxz; 
hind tarsi with two claws at tip or else with a compound claw; palpus 
with tibia and tarsus more or less depressed; hind legs usually the 
ongest MECOSTETHI 
First ventral Mcd of PNE eid ik in n froid of hind coxa; 
all tarsi with but one simple claw ; pts with tibia and tarsus cylin- 
drical, second legs thelongest . . . . .' PLAGIOSTETHI 
MECOSTETHI. 
This suborder is represented in our fauna by two families: 
1. Hind pair of coxe free at apex; spiracles obscure . PHALANGODID/E 
Hind coxz wholly united to the venter; spiracles distinct COSMETID/E 
The Cosmetide have but one genus, Cynorta, of three species, in the 
United States ; they can be distinguished as follows : 
1. Two acute spines near end of dorsal shield. . C. ornata Say (Fla.) 
Two rounded tubercles instead of spines . C. sayéi Sim.’ (S. States) 
Neither spines nor tubercles ; body with two pale spots above 
- bimaculata Banks (Calif.) 
Our Phalangodide are arranged in four genera: 
1. One compound claw to each of the four sper tarsi; palpi not as 
long as the body; eyes present : Sclerobunus 
Two simple claws to each sphere: tarsus . eee Suy 
1 Includes C. albolineatus Scerensen. 
