22 



REPORT 108, U. S. DEPARTMENT OF AGRICULTURE. 



its generic name, which is a diminutive of Rhax, a genus of Solpugida. It is 

 probable that it is the most primitive of all existing mites, and points to 

 the close relationship of the Acarina to the Solpugida. Our common species, 

 R. -pallida Banks (fig. 13), is found tliroughout the countrA', but more commonly 

 in the north. Other species are found in Europe, Japan, Kerguelen, Chile, and 

 the arctic regions. 



Fig. 12.— Linopodcs antcnnaepes. 

 (Author's illustration.) 



Fig. 13. — Rhagidia pallida. (Author's 

 illustration.) 



Fig. U.— Tydeus: 

 Beak and legl, from 

 below. (Author's 

 illustration.) 



A European mite of tliis family, Ereynctcs Umaceum Koch, sometimes occurs upon 

 certain species of slugs {Limax), and sometimes attached to a fly (Sarcophaga). AMiat 

 appears to be the Ereynetes concolor Hald. (fig. 16) occurs in our country on both 

 slugs and snails, and runs very rapidly in an irregular manner over the animal, retreat- 

 ing (perhaps to feed) into the respiratory chamber of the snail. The tarsi terminate 



Fig. 15.~ Eupodes: Legs I and IV. 

 (Original.) 



i 



Fig. IG.— Erynetes concolor: Tarsus 

 and palpus. (Original.) 



obliquely and have a large double pad at tip, with two slender claws. Two genera, 

 allied to Alichits, are saltatorial ; one, Nanorchcslcs, occurs in the crevdces of rocks on 

 the French coast; the other, Spdcnrchcstcs, is found in ant and termite nests, one 

 species in SwcmIch, the other in South Africa; the femora axe not enlarged, but the hind 

 coxa; are liighly develoi)ed. 



