d. Aquatic species. HYDRACHNOIDEA.
e. Palpi small, three segmented, adhering for some distance to the lip; ventral suckers at genital opening or near anal opening usually present; no eyes; tarsi often end in suckers; beneath the skin on the venter are seen rod-like epimera that support the legs; body often entire. Adults frequently parasitic. SARCOPTOIDEA.
f. With tracheæ; no ventral suckers; legs ending in claws; body divided into cephalothorax and abdomen; the female with a clavate hair between legs I and II. Usually not parasitic on birds and mammals. Tarsonemidæ
g. Hind legs of female ending in claw and sucker as in the other pairs. Pediculoidinæ
To this sub-family belongs the genus Pediculoides
P. ventricosus is described on [page 69].
gg. Hind legs of the female end in long hairs. Tarsoneminæ
Tarsonemus intectus Karpelles, normally found upon grain, is said to attack man in Hungary and Russia. Other species of the genus affect various plants (c.f. [fig. 150, g]).
ff. Without tracheæ; no such clavate hair.