Heterogijna and Fossorial Hijmoioptera. 213 



(7) 10. Hcairs of tliorax clubbed in J aud ^ ; nntenufp. 



12- or lO-jointed in ^ ; 1st joint of petiole not 



elongate . . . . . . . . . . . . Lcptotliorax. 



(2) 11. Metathorax not spined in 5 and ^; niesothorax 



in (J without converging lines . . . . . . Solc)io2)sis. 



(1) I'i. Wings very dark and ciliated in ^i 1st node of 



petiole square in ^ f^nd $ • • • • • • BIyrmecina. 



Myrmica. (PL VII. figs. 5 and 6). 

 Latreille, Gen. Crust, et Ins. iv. p. 131. 



The five forms that I have described of this genus 

 hear a very close general resemblance to one another, 

 and the latest authorities, Messrs. Emery and Forel, con- 

 sider them as mere races of one species. I have no doubt 

 they are right ; but as a rule they are pretty easily dis- 

 tinguishable, and I have therefore thought better to keep 

 them distinct. 



The short apical joints to the flagellum, the last three of 

 which are not nearly so long as its remaining joints in the 

 ? and '^ , and the transverse nervure which divides the sub- 

 marginal cell in the <? and ? , distinguish this genus 

 from its allies. Labial palpi 4-jointed ; maxillarypalpi 

 6-jointed. 



(()) 1. (^ with the basal joint of the antenna half as long 

 as the da^'ellum, and also gradually curved near 

 the base; J aud ^ with the basal joint not 

 somewhat angularly and sharply bent near the 

 base. 



(3^ 9. Frontal area longitudinally striated in all the sexes sulci)iodis. 



(2) 3. Frontal area smooth and shining in all the sexes. 



(5) 4, (^ with long ei-ect hairs on the tibiae ; J with the 

 metathoracic spines not longer than they are wide 

 at the base ; § with the spines scarcely longer 

 than in the J aud the space between them 

 smooth and shining . . . . . . . . Icpvinodis. 



(4) 5, ^ with short, somewhat adpressed hairs on the 

 tibise; J with metathoracic spines much longer 

 than their basal width ; § with long spines like 

 the 5 and with the space between them rugose ruginndisf. 



(1) C. (J with the basal joint of the antennse not \ so long 

 as the flagellum, or, if half as long as the flagel- 

 lum, then with it sharply bent near the base ; 

 J and 5 with the basal joint sharply and angu- 

 larly beut near the base. 



(8) 7. (^ basal joint of antennae very short, not longer 

 than the first t'so or three joints of the flagellum ; 

 5 and 5 with the basal joint not spinose at its 

 bend.. .. .. .. .. .. .. scahrinodis. 



(7) 8. (J basal joint of antenna; half as long as the flagel- 

 lum ; sharply bent at the base; J and ^ with 

 the angle of the basal joint spinosely lobate . . lobicornis. 



