ORTHOPTERA 



249 



and the first segment of the hind tarsi is imarmed above or with only 

 one row of teeth. There is only one tympanum in each fore tibia. 

 The length of the body is less than 12 mm. 



There are many species and varieties of this genus in our fauna. 

 The following enlarged figures of two of our species will serve to 

 illustrate the form of these insects. (Fig. 269 and 270.) 



Fig. 268.- 

 mesticus. 

 ger.) 



-Gryllus do- 

 (From Lug- 



Fig. 269. — -Nemo- 

 bius fasciatus. 

 (From Lugger.) 



Fig. 270. — Nemo- 

 bius palustris. 

 (Fom Blatch- 

 ley.) 



Subfamily MYRMECOPHILIN^ 



The Ant-loving Crickets 



The members of this subfamily are very small crickets, which live 

 as guests in the nests of ants. 

 The form of these crickets is very 

 remarkable. The body is ovate, 

 greatly convex above, and wing- 

 less (Fig. 271); the hind femora 

 are ovate and greatly enlarged, 

 the cerci are long; and the ovi- 

 positor is short and stout. 



Wheeler ('00) states that 

 these crickets feed on an oily 

 secretion covering the surface of 

 the body of the ants; they also Fig- 271 —MyrmecopMla pergandei. 

 obtain this substance from the ^^'■°"' Lugger.) 

 greasy walls of the ant-burrows. 

 Apparently the ants derive no benefit from the presence of these 



