262 IMr. T. D. A. Cockerell — Descriptions and 



Meyacliile chrysothamni, sp. n. 



? . — Length 13 mm. or a trifle less. 



Black, ^vitll white pubescence, having rather a mouM-like 

 appearance on thorax ; abdomen shining, rather parallel- 

 sided, witli creamy-wiiite hair-bands; ventral scopa white, 

 black on last segment and apical third of penultimate one; 

 claws without any distinct basal tooth. Head normal; eyes 

 pale greenish grey, parallel ; vertex with a band of black 

 liair, and middle of mesothorax with a little of the same 

 colour ; clypeus shining, but closely punctured, its anterior 

 edge very thick, but not dentate ; mandibles 4-dentate ; 

 antennaj dark ; mesothorax very densely punctured ; tegulae 

 dark reddish. Wings moderately dusky. Legs black, with 

 light hair, that on inner side of tarsi pale yellowish ; middle 

 tarsi thick; hind basitarsus only moderately broadened. 

 Abdomen with hair on first two segments wholly j^alc, beyond 

 these coarse and black between the bands, as also on sixth 

 segment, which, however, is covered with pale tomentum at 

 its tip; sixth segment ordinary, not subvertical. 



Rather like 21. texana, Cresson, but the black hair does 

 not cover the penultimate ventral segment, and the last three 

 abdominal bands are very entire and conspicuous, giving the 

 insect a distinctive appearance. Tlie shining, ratlier parallel- 

 sided abdomen is also peculiar. Perhaps the closest real 

 affinity is with M. manifesta, Cresson, although this would 

 never be suggested by superficial appearances. 



Bab. Boulder, Colorado, at flowers of Chrysothamnus 

 graveolens (scopa full of bright yellow pollen), Sept. 1, 1906 

 {S.A.Rohioer). 



2Iegachile newelli, sp. n. 



$ . — Length about 11 mm. 



Very black; short, broad, with a heart-shaped abdomen ; 

 ventral scopa white (full of bright orange pollen, doubtless 

 from some species of Compositae), the last segment with 

 black bristles at the sides ; pubescence greyish white, rather 

 scanty ; the thorax seen from above is black, with a creamy- 

 white band in the scutello-mesothoracic suture, and a spot on 

 each side of it, a little in front, these markings being very 

 conspicuous ; abdominal bands present, but only moderately 

 developed. Head very broad ; flagellum inclined to be 

 reddish beneath ; clypeus very densely punctured ; man- 

 dibles \QYj broad, the teeth low and obtuse ; lower margin 

 of mandibles strongly concave ; apical joint of maxillary 



