58 



ARTHROPODS 



Classification. — The student will find the collecting of beetles ex- 

 ceedingly interesting on account of their great variety, and diversity 

 of external appearance. They may be traced to their families by the 

 following table, but the help of a specialist will generally have to 

 be secured in finding the genera and species. 



Under surface of Harpalus caliginosus illustrating the parts most 

 used in the classification which follows (after Le Conte and Horn). 



A. Antenna. 



B. Mandible. 



C. Ligula. 



D. Labial palpus. 



E. Maxilla inner lobe. 



F. Outer lobe. 



G. Maxillary palpus. 

 H. Mentura. 



I. Genae. 



K. Gula, with the 



gular sutures. 



L. Buccal fissure. 



V. Ventral segments. 



