June, 1913] AlDRICH : NORTH AMERICAN SpECIES OF LiSPA. 128 



coxae) I or more; mesopleural i in front near the protothoracic and a 

 vertical row on hind edge; sternopleural 3 (i in front and 2 behind). 

 Calypters (tegulae, squamae) rather large, conspicuous, the hind one 

 about twice as long as the other. Abdomen cylindrical, straight or 

 convex, or moderately depressed, often with spots of yellow or white 

 pollen on the last two segments; segments hairy, the hairs longer on the 

 hind edge of the segment and especially on the sides, on the fourth and 

 fifth these long hairs becoming bristle-like; hypopygium never very 

 large. Legs hairy and bristly ; the principal bristles of the front ones 

 as follows; coxae on fore side with numerous bristles not in rows ex- 

 cept on outer edge; femora with a double row on upper and outer edge, 

 and a single row on lower and outer edge; tibiae with about three 

 preapical bristles and sometimes one higher up, below the middle. 

 Middle legs: coxae hairy or bristly on foreside, femora sometimes 

 elongate and then more slender on apical third, with one or more 

 preapical bristles on the hind side above ; tibiae with one or two bristles 

 on the outer side about the middle. Hind legs : femora with a row of 

 bristles above, and another less complete on the lower and outer side; 

 tibiae with one or two bristles near the middle and several preapical. 



Wings of simple structure, third and fourth veins parallel (con- 

 vergent in some old-world species) ; no noticeable spots or clouds; 

 anterior crossvein almost behind the tip of first vein; posterior cross- 

 vein distant less than its length from the margin (on the fifth vein). 



The first comprehensive treatment of the North American species 

 was by Stein, in his important paper on N. A. Anthomyidae (Berl. Ent. 

 Zeitsch., XLII, 161-288, 1897) ; he described three new species (nigro- 

 mdculata subsequently proving to be a synonym of palposa), and 

 identified three others. Starting from this basis, the student may 

 consult two important papers on the European and palaearctic fauna 

 respectively; — Kowarz, Wien. Ent. Ztg., XI, 33-54, 1892; and Becker, 

 Zeitsch. f. Ent, XXIX, 1-70, 1904. 



My study of the North American species indicates that the avail- 

 able characters for specific separation are few but sufficient. Head 

 characters are the width of the front at the narrowest as compared 

 with the entire width of the head, the measurement being in both 

 cases at the level of the antennae or even a trifle below, where the 

 compound eyes are nearest together. The presence and coarseness of 

 hairs on the sides of the face ; presence of a black band across root 



