10 PROCEEDINOS OF THE XATIONAL MUSEUM. vol.46. 



spine at each lateral angle and two pairs of smaller spines on poste- 

 rior margin. Mesothorax tapers very slightly posteriorly; metano- 

 tal plate bears four spines very close together on front margin, of 

 which the inner pair is much the stouter — nearly as stout as those 

 upon angles of prothorax. Wings reaching seventh abdominal seg- 

 ment; breadth at the iniddle about one-tenth the length; shaded very 

 slightly with yellow; vems in fore wing extend to the tip; spines on 

 veins at regular intervals; costa 23 to 30; fore vein 17 to 22; hind 

 vein 13 to 16; scale 5; interior of scale 1 ; all spines are long, prominent, 

 and brownish; a sparse slender fringe on costa of each wing; posterior 

 fringes rather heavy and wavy. Legs pale yellow, of medium length, 

 strong, the fore femora considerably thickened; legs clothed with 

 numerous slender, light brownish spines; all tibiae armed with two 

 rather stout spines at the tip within; hind tibise with a row of five 

 spmes along inner margin near the tip. Hind tarsi bear three rather 

 conspicuous spines; a dark brown spot at tip of each tarsus within. 



Abdomen almost cylmdrical to the eighth segment, thence taper- 

 ing evenly to the rounded tip; a narrow brownish indistinct line 

 across dorsum of segments two to seven; three to four fairly stout 

 brownish spines stand out prominently on sides of segments two to 

 eight; six slender brownish spines stand in a row along posterior 

 margin of each ventral plate two to eight; tip of ninth segment bears 

 a circlet of 10 spines, of which the dorsal four pairs are strong and 

 promment; tenth segment bears a circlet of six long slender spines 

 near the tip, of which the dorsal four are the stouter and much the 

 browner; other spines on ninth and tenth segments small and incon- 

 spicuous; tenth segment conical, split open above. 



Described from four females; no males found. 



Locality, Yuma, Arizona, June, 1910. 



Food plant, cotton — collected from tips of the leaves. 



Argyle McLachlan, collector. 



Type.— C&t. No. 15723, U.S.N.M. 



Note. — This species lies very close to Euthrlps heliantJii Moulton, 

 from which it may be distinguished by the greater relative width of 

 the head, the difference in coloration of the antennae, the different 

 number of spines upon the scale, by the greater relative width and 

 length of prothorax, and by having the tenth abdominal segment 

 split open above. 



EUTHRIPS TRITICI, var. BISPINOSUS. new variety. 



Figs. 17-18. 



Female. — Length about 1.28 mm. Relative measurements of head 

 and prothorax as in Euthrips tritici. General color pale yellow, 

 shading to gray on sides of head and abdomen. Anterior wings pale 



