some Parafti'fic Bees. 35 



.intf^nnal joints larg-ely i"e'.l ; lower 



half of pleura covered with hair .... heulahe)isi^, Cldl. 



6. Legs blaciv 7. 



Lega red 8. 



7. Larger; black area on first segment 



narrow, /. e. not much produced 



laterally nevadensis, Cre.s.?. 



Smaller; black area ou first segment 

 very broad donatus, Smith, 



8. Scutellar teeth long and sharply 



pointed, at least partly red ; dark area 



on disk of first segment very small. . 9. 



Scutellar teeth shorter, entirely black . 10. 



9. Larger; mesothorax mainly red .... jnmarum, CkW. 

 Smaller; mesothorax black mesilhe, Ckll. 



10. Area on first segment a broad trans- 



verse band 11. 



Area on first segment small, not pro- 

 duced laterally ; size lai'ge tc.iroim, Cress. 



11. Tegulfe clear light red; mesothorax 



with an anterior patch, not two dis- 

 tinct stripes occidentalis, Cress. 



Tegulse dark reddish to dark fuscous ; 



mesothorax with two distinct stripes. 12. 



12. Larger; labrum entirely black heliantlii,Vy,oh.,yAV. 



Smaller; labrum with two red spots. . helianthi,Iloh. 



Males. 



Abdomen with eight club-shaped light 



marks verbesina, Ckll. 



Abdomen not so marked 1. 



1. Markings of abdomen orange, white on 



sixth segment naidlanm, Ckll. 



Markings of abdomen white or pale 

 cream-colour 2. 



2. Mark on first abdominal segment semi- 



lunar 3. 



Mark on first abdominal segment a 



traoisverse band 4. 



3. Legs black concolor, Rob. 



Legs red lunatus, Say. 



4. Bands on second to fourth segments 



interrupted in middle line ; size 



small ; femora black olympieUus, Ckll. 



Bands on third and fourth segments, at 

 least, entire ; hind femora, at least, 

 red 5. 



5. Lower part of pleura bare 6. 



Lower part of pleura covered with hair. 7. 



G. Larger ; tegulre clear red ocddeiitcdis, Cress. 



Smaller ; tegulfe darkened helianthi, var. arizonensis, 



7. Anterior femora red; abdominal mark- [Ckll. 



ings white {socom(e, Ckll. 



Anterior femora black ; abdominal 

 markings cream - colour ; antennie 

 black Cressoni, var. frasercB, Ckll, 



3* 



