THE PHASMID.E, OR WALKTNGSTICKS. OF THE rNITED 



STATES. 



By Andrew Nelson Caudell, 



Of the Depurtment of Agriculture. 



Tho Phasmidae is one of the most interesting families of the order 

 Orthoptera. It is poorly represented in the United States, and the 

 species, being mimetic in nature, are not commonly met with. Our 

 forms are all apterous and are confined in their distribution to the 

 southern half of the country, with the exception of the species of the 

 genus Dinpherontem^ one of which extends into Canada. The name 

 " walkingstick" is commonly applied to these insects, and the conunon 

 northern species, T)i<(pJieromerafeiiiorafa Say, is the best known rep- 

 resentative of the family. There is a popular belief extant in some 

 parts of the country that these insects are very poisonous to stock when 

 eaten by them. For this reason they have been called the ''mule 

 killer,'' though this name is more often applied to species of the family 

 Mantida-, which ai-e said to be especially fatal to that useful animal. 

 Among other popular names given to the walkingsticks are DeviFs 

 riding horse. Prairie alligator. Stick bug. Witch's horse. Devil's darn- 

 ing needle. Scorpion, and Musk mare, the latter applied only, I believe, 

 to the species of the genus AniHomorpha. 



Nowhere do we tind more striking instances of protective resem- 

 blance than those ati'orded l)y members of this family of curious insects. 

 In the tropics, where these insects abound, such amazing adaptations as 

 the wonderful Walkingleaf, Fhyllmin scythe, and other large, winged 

 forms are found. In the United States the specries are all wingless 

 and mimic different kinds of twigs, especially so the more slender 

 species of the genera Diaphenwiem^ Bacnnculm, and ParalxwilJux. 



The Phasmidiy are insects of very deliberate motion, especially the 

 females. They do not depend upon locomotion for protection from 

 their eneiuies, but to their deceptive resemblance and, in some cases, 

 to the power of emitting an offensive spray from si)ecial glands situated 

 on the prothorax^. 



Proceedings U. S. National Museum, Vol. XXVI-No. 1335. 



