A. C. OUDEMANS, NOTES ON ACARI. 255 
times longer than wide, posteriorly rounded and scarcely incised 
in the middle. Texture smooth in the hard parts; finely 
wrinkled in the weak parts. 
Dorsal side (Fig. 36) Here we observe a distinct divis- 
ion between a prosoma and metasoma (cephalothorax and 
abdomen). The anterior dorsal shield occupies nearly 
the whole dorsal side of the prosoma, leaving however a 
narrow unprotected band of skin laterally and posteriorly. It is 
almost trapezoidal, slightly wider posteriorly. Its lateral edges 
behind legs I are straight; its posterior edge is provided with 
three scallops. The division of this shield in three pieces is 
scarcely discernable, if any. The two chitinous ridges behind 
the mandibles converge a little backward. The posterior 
dorsal shield occupies the greater part of the dorsum 
of the metasoma; laterally it is, however, concave, so that its 
form is almost dumbbell-shaped, be it not truncate anteriorly. 
The anterior lateral shields only visible as a dark 
marginal stripe behind the trochanteres Il; the middle 
lateral shields fused with the posterior lateral 
shields, visible as a marginal light brown stripe. Between 
these lateral double-shields and the posterior dorsal shield a 
white band of unprotected (wrinkled) skin. Hairs: the same 
as in the deutonympha, except that you will observe between 
the openings of the excretory glands and on the dorsal shield 
a pair of minute hairs which are not present in the deuto- 
nympha. The longest of the posterior hairs are longer than the 
metasoma. The copulation-hole is not dorsal, but 
ventral, yet postanal, lying under a thin membrane which 
is expanded between the abdominal lobes (for there is a median 
incision). The tube, however, is very short in this species. 
The ventral situation of the copulation hole 
was reason that Trouessart ascribed parthe- 
nogenesis to this species. In fig. 36 I have delinea- 
ted the (interior) copulation tube. 
