18 



cultivated vegetation, hence need not be taken into serious 

 consideration in a treatise on destructive locusts. The f olow- 

 ing three or four species maj^ be looked for in the territory 

 mentioned above. 



TABLE FOR DETERMINATION OF GENERA. 



A. Fastigium of the vertex very narrow, scarcely or not at all ])rojecting 

 in advance of the eyes. EUMASTAX Burr. 



A A. Fastigium of the vertex wider and more or less ])rojectlng in ad- 

 vance of the eyes. MASYNTES Karsch. 



GENUS EUMASTAX, BURR. 



This generic name has recently been suggested by Mal- 

 colm Burr (Anales de la Sociedad Espanola de Historia 

 Natural, Vol. XXVIII, 1899) in place of Mastax Perty, which 

 had been used several years before in Coleoptera. This 

 being the tyi3ical genus of the sub-family necessitated the 

 changing of that name also. 



TABLE FOR THE DETERMINATION OF THE SPECIES. 



A. Apex of the vertex above the eyes, when viewed from the side, not 



visible. Tegmiua and wings fully developed. Posterior femora 



irregularly black spotted. pardaliua Burr. 



A A. Apex of the vertex above the eyes when viewed from the side 



])lainly visible. Detiexed lobes of the protonum with the anterior 



angle obtuse. versicolor Burr. 



Eumafitax pardallna Burr, Essai sur les Eumastacides, p. 51. 



This insect was described as coming from Paraguay, and 

 is liable to occur in northern Argentina. 



EumoHtax versicolor Burr, loc. cit. p. 54, also a Paraguayan 

 species, and might likewise occur in the Territory of the 

 Chaco. 



GENUS MASYNTES, KARSCH. 



TABLE FOR THE DETERMINATION OF THE SPECIES. 



A. Tegmina lobiform, elliptical, the apex broadly rounded. Pronotum 

 truncate behind, the middle minutely notched. 



Borellii Giglio-Tos. 



AA. Tegmina and wings perfectly developed. Pronotum "rounded 



behind, the middle not notched. tigTi.s Burr. 



iVmyntes Bm-elUi Giglio-Tos, Boll. Mus. Torino, Vol. XII, 

 No. 802, p. 17, 1897. 



