1903.] NATURAL SCIENCES OF PHILADELPHIA. 589 



yellow spots on each extreme side of third and fourth abdominal seg- 

 ments. Third antennal joint considerably shorter than fom'th. 



In a paper sent to Annals and Mag. of Nat. History, I have described 

 a number of red species of Nomada from Corvallis, Ore.; but have 

 given no table for their separation. The following table separates the 

 females seen from Corvallis, in which red is the preponderating color : 



1. Mandibles bidentate; abdomen with yellow spots on second seg- 



ment only, or none; third joint of antennae as long as fourth; 



metathorax with a black median band 2. 



Mandibles simple, 5. 



2. Larger; abdomen dark red; third submarginal cell narrowed 



almost to a point above; first abdominal segment with a black 



mark on each side, 3. 



Smaller; third submarginal cell not so much narrowed, . . 4. 



3. Second segment with no distinct yellow spots (May 28), 



hella, Cress., var. 

 Second segment with distinct yellow spots (May 9), 



hella, Cress., var. 



4. Abdomen shorter, dark red (April) rhodomelas.CkW.'? 



Abdomen longer, light red (May) W'ayi, Ckll. 



5. Abdomen with black bands (June), .... nigrocinda, '^imih.. 

 Abdomen without black bands, 6. 



6. Abdomen with large yellow spots on second and third segments, 



more or less of a band on fourth, etc. ; third antennal joint about 

 equal with fourth; a little yellow at lower corners of face (^lay 



and June), lewisii, Ckll. 



Abdomen with very small yellow spots or none, and no band, 7. 



7. Abdomen without yellow spots, 8. 



Abdomen with yellow spots (4 or 6) ; yellow^ at lower corners of 



face; third antennal joint shorter than fourth, .... 10. 



8. Size larger, about 10 mm. long; third antennal joint almost as long 



as fourth ; no yellow at corners of face ; sides of abdomen with 



suffused black marks (April), clarh'i. Ckll. 



Size smaller, about 8 mm. long, 9. 



9. Yellow at lower corners of face ; third antennal joint not more than 



half length of fourth; sides of abdomen inclined to be black- 

 spotted (INIay, June) astori, Ckll. 



No yellow at lower corners of face; thiixl antennal joint at least as 

 long as fourth; abdomen dark red, its sides without black marks 



(;\Iay) corvallisensis, Ckll. 



10. Base of abdomen wdth a black mark in middle, or black right across ; 

 third antennal joint not much shorter than fourth (May, June), 



oregonica, Ckll. 



Base of abdomen without a black mark in middle; third antennal 



joint much shorter than fourth (May, June), . ulti'ma, Ckll. 



Nomada ultima taraxacella, subsp. n. 



9 . — Length 7 mm., red; similar to ultima, but face narrower; meso- 

 thorax red without any black stripes (three black stripes in vl(ima); 



