308 



DR. JOHNSTON ON THE ACARIDK5? OF BERWICKSnillR. 



16. Cheyletus eruditus, Latr. 

 Cheyletus eruditus, Latr. Gen. Crust, et Ins. i. 1 53. Lam. 

 Anim. s. Vert. v. 58 ; 2(le edit. v. 75. Latreille in Cuv. Reg. 

 Anim. iv. 285. Risso I'Europ. merid. v. 181. Leach in Edin. 

 Encyclop. vii. 414. Stark Elem. ii. 206. Koch. Uebers. Arach- 

 nid. 78, tab. 9, fig. 45. Gervais in Walck. Insect. Apt. iii. 

 165. — Acarus eruditus, Turt. Gmel. iii. 707. 



Desc. Mite minute, about half a 

 line in length : Head distinct and 

 separate, triangulate, much narrow- 

 er than the body (Fig. 1) : Eos- 

 trum declivous, conical, and armed 

 with a bristle on each side a little 

 below the truncate apex (Fig. 1) : 

 Palpi mandibular, very large and 

 powerful, extended considerably be- 

 yond the rostrum, arising on each 

 side of the head below the rostrum, 

 2-jointed, the basal joint sub-cylindrical, slightly kneed, a 

 long bristle on its proximal side, 2d joint oblique and con- 

 tinued into a process on the outer side whence originates a 

 curved acute finely proportioned cla"\v, immediately within 

 which there are two slender setie, and within these again a 

 pair of semipectinated processes or combs, the innermost 

 one scarcely half the size of the other (Fig. 2) : Body ovate 



or rather shaped like a coifin, soft, obtuse and rounded^ at 

 both ends, the back flattened, even and naked, the sides co- 

 riaceous and of a yellowish-brown colour, while the front, 

 the middle, and the anal region are soft and opaque white : 

 Legi 8, slender and tapered, of a clear watery-white colour, 



