NO. 1310. NORTH AMERICAN THYSANOPTERA— HINDS. 139 



one lono-, stout spino. Leg's rather short and thick. Wings quite 

 long- and of medium breadth; costa ])earing- a fringe; veins ])earing a 

 few short spines. Terminal segment of al)domen in female elongated 

 somewhat and approaching a tubular form, split open above; each 

 side bears a short, extremely stout spine and similar stout spines are 

 borne upon the sides of the eighth segment. 



Male entirely wingless. End of abdomen bluntly rounded; ninth 

 segment bears a stout spine at middle of each side and a pair of simi- 

 lar spines stands closely together near the dorsal line above. 



Species of this genus move slowly and have no power of leaping. 



I found only the new species avenee- of the genus. 



LIMOTHRIPS AVEN^, new species. 

 Plate I, figs. 10-12; Plate 11, fig. l.'!. 



Fcindle. — Lengtli 1.57 mm. (l.-iSto 1.06 mm.); width of mesothorax 

 0.28 nun. (0.26 to <».3() mm.). Form elongated, slender. General color 

 dark yellowish l)rown. 



Head a little longer than wide, tapering a little anteriorly; cheeks 

 very slightly arched; surface of head not at all, or l)ut very faintly, 

 cross striated and bearing a few scattered minute spines; front strongl}^ 

 arcuate, produced considerably between bases of antenna^; color of 

 head dark brown. Eyes of moderate size, black with 3^ellow margins, 

 triangular above, protruding slightly; ocelli fairly well separated, 

 anterior one smallest, pale yellow with very dark red crescents on 

 inner margins. Mouth cone short and moderately thick; maxillary 

 palpi short, only two segmented. Antenna rather short, about one 

 and one-half times as long as the head, considerably separated at 

 bases; relative lengths of segments as follows: 



I 



Segment one much wider than long; two cup-shaped; three to five 

 clavate; .six fusiform; seven and eight slender, cylindrical; one and 

 two dark brown; three to eight shading graduall}^ from pale brownish 

 gray to more or less dark brown; outer angles of three and four strongly 

 developed (three especiall}' so, though obtuse), and each bears one long 

 pointed sense cone; six also bears one long, slender sense cone on inner 

 side at two-thirds its length. 



Prothorax a little shorter than head and about one and one-third 

 time.s as wide as long; sides diverging from head posteriorly; only 

 one long stout spine at each posterior angle; other spines scattered and 

 minute; transverse margins nearly straight; sides slightly rounded; 

 concolorous with head. Mesothorax about one and one-third times as 

 wide as prothorax; metathorax aljruptly narrower; sides nearly par- 



