270 PROCEEDINGS OF THE ACADEMY OF [PaRT II 



Carcarana, Santa Fe, Argentina, 2 cf, type and paratype, 4 juv. 

 d", 2 juv. 9, [Hebard Cln.]. 



Rosario, Santa Fe, Argentina, (H. Stempelmann,) 1 d^, paratype, 

 fHebard Cln.]. 



Vicinity of Buenos Aires, Buenos, Argentina, February, 2 cf, 

 2 9 , allotype and paratype, [Paris Museum]. 



Ischnoptera argentina new specie?. Plate XI, figures 4, 5 and 6. 



This species is very closely related to/, rufa (De Geer), differing 

 in important features of the male genitalia, the distinctly less red- 

 dish general coloration of the males and differently shaped female 

 supra-anal plate. ^^ 



It is probable that it was the present, or a related undescribed 

 speces, which Giglio-Tos has recorded as rufa from San Lorenzo, 

 Argeintina and San Francisco and Caiza, Bolivia. ^^ 



Rehn's records of 7'ufa from Mieiones, Argentina, are based on 

 very light specimens of I. ignohilis Saussure."" 



Type: cf ; San Nicolas, Buenos Aires, Argentina. November 5, 

 1897. [Hebard Collection Type no. 671.] 



Size medium large, form moderately stout. Head with inter- 

 ocular space appreciably narrower than that between the ocelli, 

 (varying in male paratypes to nearly that width). Ocelli distinct, 

 flattened surfaces of ocellar areas slanting rather strongly mesad, 

 very slightly more so than in rufa. Maxillary palpi rather short. 

 Pronotum with discal sulci decided. Tegmina and wings elongate, 

 more so than in rufa, much as in /. angustifrons Hebard. Supra- 

 anal plate produced; lateral margins weakly convergent, distal mar- 

 gin transverse, three-quarters length of plate; surface subchitinous 

 in a large transverse oval, just proximad of distal margin; ventral 

 surface with very short, stout bristles, near sinistral margin and on 

 a moderately prominent convex area adjacent to the dextral margin 

 of the subchitinous area. Paired plate beneath supra-anal plate spe- 

 ciaUzed: at base of sinistral style produced mesad in a chitinous re- 

 curved spine, the dorso-proximal portion of which is subchitinous; 

 at base of dextral style produced mesad in a heavy shafted, chitinous 

 spine, over twice as long, directed caudad and then curving broadly 

 inward to its aciculate apex. Titillator with apex similarly special- 



^' Though the female supra-anal plate varies in having the lateral margins 

 straight convergent to rather broadly concave convergent in rufa (upon which 

 apparent difference was based Saussure's consobrina, a synonym of rufa occi- 

 dentalis Saussure), the lateral emargination of this plate shown by females of 

 argentina is of a different quality and much more decided than is shown by any 

 of the large series of the females of the races of rufa before us. 



M Boll. Mus. Zool. Anat. comp. Univ. Torino, XII, No. 302, p. 5, (1897). 



ssproc. Acad. Nat. Sci. Phila., 1913, p. 270, (1913); ibid., 1915, p. 272, (1915). 



