ACARI 567 



second pair of the posterior shield (1882, p. 55) « la posteriore 

 (scudo) ha due setole pennate suU' orlo posteriore presso la 

 linea mediana e due altre un po innanzi ed ail' esterno délie 

 precedenti ». 



The shape of the epistomais verynearly the same, the only 

 différence — in G. mucronatus the edge has 4 small teeth (1882, 

 pi. 5, fig. 9), while in P. brevispinosiis it has only two — is no 

 greater than that not inf requently f ound in différent individuals 

 of the same species. 



The mandibles differ also sUghtly, not with regard to their 

 shape, but as to their dentition ; but hardly enough to imply 

 a spécifie différence, the more so as Canestrini's figures, 

 and those of Berlese, also differ shghtly from one anotlier, and 

 together with P. brevispinosus form an unbroken séries, in 

 which Berlese's spécimen occupies an intermediate position. 



The mandibles of ail three spécimens hâve 4 teeth in the 

 lower jaw, equidistant, and of subequal size. In . Canestrini's 

 spécimen the upper jaw has 6 teeth besides the terminal one ; 

 ail of uniform size. In Berlese's drawing we notice that the 

 posterior tooth has moved farther back ; that the next two 

 are set more closely together than the others; a*id that the 

 next firsthas diminished in size, as compared with the mandible 

 dehneated by Canestrini. 



In P. brevispinosus the posterior tooth is reduced, and the 

 next first and second, wliich in Berlese's spécimen were set 

 closely together, hâve quite coalesced and become so reduced 

 in size as only to enable us on close examination to notice two 

 extremely minute teeth, 



The ventral side of C. mucronatus has not been described 

 by Canestrini. Berlese's description is very superficiel, and 

 his drawings do not impress one as being very accurate, but 

 rather eut and-dried (1). 



( 1 ) Thus, the e p i g y n i a 1 s h i e 1 d is almost a quadrate, a feature'uuknowu iii the ParasUinae : 

 luost of the sternal hairs, and the two epigynial hairs, are missing ; and the hairs of the ventri-anal 

 hairs obvioiisly placed at raiidom, otc-. 



ARCH. DE ZOOL. EXP. ET GÉK. — 5"= SÉRIE. — T. VIII. — (VIIJ. 40 



