FIELD BOOK OF INSECTS. 



small and not numerous species are rarely noticed. They 

 are the MONOTOMID^E, DERODONTID^E, BYRRHID^E, GEO- 

 RYSSID^E, and HETEROCERID^E. 



The remainder of the Polymorpha are known as SERRI- 

 CORNIA. "This series is primarily distinguished, as 

 its name indicates, by the serrate or saw-tooth character 

 of the antennas. The serrate antenna is, like the filiform, 

 usually slender and of nearly the same width throughout, 

 but differs in having each joint project more or less in- 

 wards, this projection being sometimes so long as to form 

 what is called the pectinate, or comb-toothed antenna" 

 (Blatchley) . However, Nature is not clear-cut in any of her 

 divisions. Apparently she does not use a card catalog. 

 "System" is a human invention. Passing by the DASCYL- 

 LID^E and RHIPICERID^ we come to a large family some 

 members of which most people have noticed. 



ELATERID.E 



With the exception of the subfamily Eucneminse, which 

 is considered by some authorities to be a separate family, 

 these beetles have a unique method of getting on their 

 feet if, by chance, they are on their back. They spring 

 into the air and turn over as they go. This trick has won 

 them various names such as Skip Jacks, Click Beetles, 

 Spring Beetles, and Snapping Bugs. Once, in Arizona, 

 I had a guide who had never noticed them before. I 

 made some of the species, which came to the camp light, 

 perform. He immediately christened them Break-backs 

 and began tu count up how much he would win, after he 

 got back to Tucson, by betting on "whether they would 

 or wouldn't land right side up." I advised him to put 

 his money on "would" and for nights, thereafter, he 

 hung around my moth-tent, turning Elaterids on their 

 backs to see whether they would or wouldn't. I do not 

 know how he made out. 



Break-backs is really not a bad name, as their pronotum 

 is very loosely joined to the rest of the body. Its hind 

 angles are prolonged backward but the elytra slope so 

 that the back can be bowed. This is done when the 

 beetle finds itself wrong side up and then the body is 



306 



