218 



F. W. EDWARDS. 



Claws toothed ; thoracic markings as in ornatum . . . . . . . . 6. 



Claws simple ; thoracic markings difierent, or absent . . . . . . 7. 



Membranous area of pleura with soft hairs . . ornatum var. nitidifrons, n. 



Membranous area of pleura bare 



7. Face black, shining, like the frons ; legs mainly black . . 

 Face grey ; legs more extensively pale 



8. Thorax almost dull, with coarser pubescence 

 Thorax somewhat shining, with much finer pubescence 



9. Basal two-thirds of hind tibiae clear yellow 

 Basal half of hind tibiae yellow, but less sharply distinguished from the black 



apical portion . . . . . . . . . . 10. 



moaticola, Fried. 

 tuberosum, Ldst. 



. . 8.. 



. . 9. 



..11. 

 reptans, L. 



Fig. 1. Head markings of SimuUum larvae (the markings vary a good 

 deal in intensity in most species ; individuals have in each case been 

 chosen which showed the markings most strongly developed. The figures 

 are somewhat diagrammatic and not strictly to scale) : a, 8. ornatum ; 

 h, 8. variegatum and 8. monticola ; c, 8. suhornatum ; d, 8. reptans ; 

 e, 8. reptans var. galeratum; f, 8. morsitans; g, 8. venustum; h, 8. argy- 

 reatum ; i> 8. equinum ; j, 8. latipes ; k, 8. aureum ; I, 8. angustitarsis ; 



m, 8. subexcisum. 



10. Kather less than basal haK of mid tibiae yellowish 



venustum, Say {=austeni, Edw.). 

 Bather more than half of mid tibiae yellowish . . . . morsitans, Edw. 



11. Thorax brightly shining ; front coxae reddish . . argyreatum (Mg.) Ldst. 

 Thorax less shining, with traces of the two greyish longitudinal stripes seen 



in the male ; front coxae blackish . . argyreatum var. sericatum- Mg. 



12. Vein B., ^ 3 absent (normal) ; second joint of hind tarsi more or less excavated 



above near the base . . . . . . . . . . . , . . 13. 



Vein B2 + 3 present; second joint of hind tarsi cylindrical ; claws simple and 

 rather smaU . . . . . . . . hirtipes, Fries. 



