618 IVAR TRAGARDH 
Ventral side (fig. 146). The sternal shield is very little darker than 
the other shields and has no sculpture; it is slightly longer than it is wide in 
the middle, on a level with the 2nd pair of bristles, and the posterior margin forms 
an even curve forwards, extending to the middle of coxe III, with blunt pos- 
‘terolateral angles. There are two pairs of large, transverse, slit-like pores, one 
closely behind bristle I, the other halfway between bristles II and II. .The 
sternal hairs are of the same length. 
Metasternal shield narrow, widening backwards, extending from the 
middle of cox III to a little beyond the middle of cox IV, with one pairs 
of hairs, as long as the sternal hairs. 
Geniti-ventral shield with the genital part apparently set off from the 
rest by a straight, transverse furrow, tongue-shaped and with numerous longi- 
tudinal, slightly radiating striz. 
Ventral part broad, with rounded sides, posteriorly with rounded incision, 
where it is contiguous with the anal shield, 7/3 as long as it is wide, without 
any sculpture. There are 4 pairs of pointed bristles placed as fig. 146 shows. 
Since BERLESE in his latest description lays much weight on the distance be- 
tween the bristles I have measured this: I 178 pw, Il 304, III goop, IV 285 uw. 
The legs (fig. 146). Coxz I with two stout bristles, the posterior one of 
which is twice as long as the anterior one; coxe II—IV with the usual stout 
bristle. The legs do not exhibit any remarkable features. 
Mouthparts. The epistome I have not been able to see plainly; the 
hypostome does not exhibit any characteristic features. The mandible (fig. 
147): lower jaw strongly curved at the top, with large terminal tooth behind 
which there are two conical teeth, close together; upper jaw shorter and 
more slender than lower jaw with more slender terminal tooth and further back 
two broad, rather short teeth. 
Loc.: Juan Fernandez. On Rattus rattus; numerous females. 
25. Urobovella bicarinata n. sp. — Figs. 148—157. 
This species is through its peculiar shape, blunt anteriorly, pointed pos- 
teriorly, and through its polished cuticle and strongly arched dorsal shield sufficiently 
well characterized as belonging to the genus Uvrobovella BERL. It is true that 
there is no distinct dividing line between the ventral and anal shield in the 
present species which in this respect does not agree with the original diagnosis 
of the genus given by BERLESE (Acari nuovi. Manipulus I. 1903, p. 249) 
which is as follows: »Scutum anale a metapodies seiunctum». But, on the other 
hand, BERLESE already in 1904 somewhat altered his views as to the import- 
ance of this feature. In the key which he gives of the genera of the fam. 
Uropodide (p. 325) he writes: »Linea metapodiea nulla (Metapodium integrum, 
totem ventrem occupans, vix a scuto anale seiunctum). And in his diagnosis 
of the genus (1. c. p. 336) he writes: »Anus plerumque in scuto suo lato, linea 
plus minusve integra (in U. pandata evanida) transversa, ano propinque a scuto 
entrale distincto». 
