282 :,[r. T. D. A. CockexaW—Descn'ptums and 



'^\■^y 12, bv sweeping herbage {Cockerel/). It runs in my 

 table of Perdita (Proc. Acad, Nat. Sci. Philad. 189o) to 

 7'. maculipes, from which it is easily known by the dark 

 brown stigma, the pleura with only an oblique yellow band, 

 and the abtlominal bauds not united at sides. The dark 

 mark on anterior tibia is small, and if the dark markings 

 on anterior and middle legs were absent it Mould run to the 

 vicinity of salicis, n'UiJella, and exclumans, where it would 

 leadily be known by the dark stigma. The face is pale 

 yellow, and the upward extension of lateral marks is like a 

 closed hand with a very short index-finger jjointed ; there is 

 a yellow band along lower half of posterior orbits. The 

 second s.m. is not so greatly narrowed above as in the type 

 female. The ventral surface of the abdomen is yellow 

 without markings. 



Perdita blrkmanni, sp. n. 



? . — Lengtli 4 mm. or slightly over. 



Head and thorax dark bluish green, dullish, only slightly 

 hairy ; head ordinary; elypeus (except the u^^ual dots and 

 a pair of brownish bars), a very small transverse siipra- 

 clypeal mark (sometimes having the form of a letter C), 

 lateral marks (broad below, narrowed above, ending obtusely 

 on orbital margin at level of antenna;), labrum, and mandibles 

 (except the rufescent apices), all yellow ; cheeks without 

 yellow; autennai rather long, flagellum i)ale fulvous be- 

 neath ; tubercles with a [)ale yellow mark ; tegulse testaceous. 

 Wings strongly dusky, outer r. n. and t.-e. pallid and weak. 

 Legs dark brown, Mith the knees, and anterior and middle 

 tibiae in front yellow. Abdomen with a yellow mark at 

 each side of first four segments, those on first small, the 

 others pcjiuted mesad, not or hardly oblique ; venter brown. 

 The stigma is sepia, without a hyaline centre. 



Nab. Fedor, Texas, June 1 (Birhnann, 89). Two 

 specimens. 



In my tables of Perdita this runs to P. a finis, var., but it 

 is known by its small size and other characters. It is much 

 smaller than P. octomuculata, Say, and has the lateral face- 

 marks differently shaped, without the strong inner angular 

 notch. Among the Texas species it falls ch^se to P. jonesi, 

 Ckll., but differs by being smaller, with the yellow marks 

 on third and fourth abdominal segments transverse (not 

 oblique), supraelypeal mark present, anterior tibiae entirely 

 vellow in front. 



