NOTES AND DESCRIPTIONS OF NORTH AMERICAN 

 PARASITIC HYMENOPTERA.— IX.* 



By Charts T. Brues. \ 



FAMILY ICHNEUMONIDJE. 



Subfamily Cryptin.f. 



Pezomachus Qravenhorst. 



The small wingless members of this genus of Cryptinae are 

 very abundant and have been described in great numbers by Eu- 

 ropean entomologists. As early as 185 1 Forster 1 enumerated 

 over 200 species from Europe, and although many of these are of 

 extremely doubtful specific value, a great many continental spe- 

 cies exist. Very recently Morley 2 lists 58 from the British Isles, 

 so evidently the thirty or forty known North American forms 

 represent but a fraction of our fauna. In a previous paper I at- 

 tempted to give a table for the separation of the then known 

 forms"' and following is another to aid in the identification of the 

 ones added in the present paper. 



Key to the new species of Pezomachus here described. 



1. Metathorax with a complete transverse carina separating- its 

 dorsal and posterior surfaces 2. 



Metathorax without such transverse carina P.cockerelli. 



2. Petiole of abdomen with more or less distinctly projecting an- 

 gular tubercles or teeth at the spiracles 3. 



Petiole of abdomen with ho trace of spiracular tubercles 7. 



3. Postpetiole longitudinally aciculated ; antennae 20-21 jointed 



. . P.foersteri. 



Postpetiole shagreened or punctulate 4. 



4. Males 5. 



Females 6. 



5. Antennae 24-jointed P.urbanus.. 



Antennae 29-jointed P.fenestralis. 



1 ) Monographie der Gattung Pezomachus. Berlin, Verlag dor Nicolai'- 

 scheh Buchhandlung. 



2) The Ichneumons of Great Britain, Vol. 2. Plymouth, 1907. 



3) Trans. Amer. Ent. Soc, Vol. 29, pp. 119-121 1903. 



* Contributions from the Entomological Laboratory of the Bussey Insti- 

 tution, Harvard University. No. 26. 



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