ODONATA OF BAJA CALIFORNIA. 52 S 



Total length S 38.5-41, ? 40-43. Abdomen S 27.5-29.5, 

 ? 28.5-31. Hind wing (S 28-31, $ 29-32. Pter. 3.5-4. 

 Sup. app. $ 1.5., app. ? .8. 



Summary of differences between rufina-vis Bnrm. and sterilis: 

 rufinervis. sterilis. 



10 reddish-yellow. black. 



9 reddish-yellow, with a mid-dorsal and a lat- 

 eral black stripe. black. 

 Veins red. black. 

 Hind wings yellowish from base to triangle, yellowish from base to 

 with two dark brown basal streaks. first antecubital, no 



basal streaks. 



17 6 San Jose del Cabo, October, 1893, G. Eisen, are 

 also apparently to be referred to s/er//is, although at first 

 the writer supposed them to be adult velow The differ- 

 ences between velox and sterilis are so slight as to render 

 their distinctness as species very doubtful. These 176 

 have frons and vertex dark metalHc blue; thorax and ab- 

 domen either pruinose, or with pale markings more or 

 less obliterated, such traces as still persist agreeing with 

 those of either sterilis or velox. Hind wings brownish at 

 extreme base, but the apices of the wings barely edged 

 with brown (only to about the wddth of one cell); ante- 

 rior lamina projecting but little, hairy; hamule not bifid, 

 similar to that of sterilis as above : genital lobe longer 

 than wide, projecting as far or nearly as far as the ham- 

 ule, apex rounded; superior appendages black, slightly 

 longer than 9, thickened in the apical third, the thickened 

 part with about five inferior denticles, apex acute; infe- 

 rior appendage about one -eighth shorter, subtriangular ; 

 front wings with 13-16 antecubitals, 8- 11 postcubitals, 

 triangle with one cross -vein, internal triangle 3 -celled 

 (4-celled in 2 ,5 and one wing of i 5 ) ; hind wings with 

 10- 1 1 antecubitals, 11- 14 postcubitals, triangle free. 

 Abdomen 27-31. Hind wing 30-34. 



Distribution of sterilis. Mexico (Baja California, as 



