104 PROC. ENT. SOC. WASH., VOL. 24, NO. 4, APR., 1922 



2. Corium bright yellow, clavus and apical part piceous black. Length, 



3>^ mm. (Is. Grenada) armatus Uhler. 



- Corium entirely nigro-piceous and shining throughout. Length 5 mm. 

 (Panama, Colombia) vittativentris Stal. 



3. Posterior lobe of pronotum rufo-testaceous, trimaculate with black. 



Corium fuscous with pale costal margin, inner field opaque. Length 



5% mm. (Mex., Guat., Panama, Brazil) trimacula Stein. 



-Posterior lobe of pronotum entirely nigro-piceous. Corium pale tes- 

 taceous, apically infuscated, shining throughout. Length 3y mm. 

 (Texas) nigrolobus, n. sp. 



Oncerotrachelus pallidus, n. sp. 



Color pale stramineous except outer marginal vein of membrane which is 

 lightly infuscated and the apical portion of the venter which is slightly em- 

 browned, as is the membrane. 



Compared with 0. acuminatus Say the body parts and appendages are less 

 densely pilose, the antennae and legs being almost entirely devoid of the long 

 hairs so distinctive of that species. The head is more prolonged before the 

 eyes, these being relatively larger; the posterior lobe of head being slightly more 

 globose dorsally and laterally. 



Size larger measuring from l-1]/2 mm. long. 



Described from four specimens. Type 9 Sabinal, Tex. 

 (collected by F. C. Pratt); Paratypes ? Zavalla Co., Tex. 

 (coll. by Hunter and Pratt) and 29s from Victoria, Tex., 

 Collection of the U. S. Nat. Museum (Cat. No. 25204). 



Easily distinguished from 0. acuminatus Say by differences 

 in size, coloration and pilosity. Say's species is always of a 

 flavo-testaceous color with distinct fuscous markings above 

 and below. Judging from the artist's figures PI. XI, figs. 

 8, 8 a , Biol. Cent. Amer., the specimens from Mexico and 

 Central America referred to by Champion, p. 180, may in all 

 probability be referred to pallidus. 



THREE NEW SPECIES OF PECULIAR AND INJURIOUS SPIDER 



MITES. 



BY H. E. EWING, U. S. Bureau of Entomology. 



Of the large number of spider mites that recently have been 

 sent to the writer for determination, three species are somewhat 

 remarkable; one for the dimorphism shown by the male, 

 another forjits wonderful plumo_se and foliaceous coat of setae, 

 and the third for its gall-making habit, its peculiar mouth-parts 

 and its possession of but six legs in all instars. The latter 



