538 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iii 



Sternites: Polished, without postmedian rows of setigerous punc- 

 tures at lateral third of segments III to VI. 



Terminalia: Genital capsule polished, with scattered minute 

 punctures more abundant laterally, apical margin nearly straight or 

 faintly sinuate laterally, gonostylus as illustrated (fig. 246). 



Length of body: 8.85(8.38-9.37). 



Female: Similar to male, subapical impression of pronotum less 

 extensive. 



Head: Length-width ratio, L47(1.43-1.56) :2.31(2.25-2.41); inter- 

 ocular width, L41(1.36-1.44). Antennal segments: I, 0.43(0.40- 

 0.46); II, 0.27(0.25-0.31); III, 0.53(0.44-0.60); IV, 0.50(0.47-0.56); 

 V, 0.53(0.50-0.60). Labial segments: I, 0.92(0.86-1.06) ; II, 1.27(1.23- 

 1.36); III, 1.16(1.10-1.23); IV, L03(0.94-l.ll). 



Pronotum: Length-width ratio, 3.04(2.85-3.42) :4.99(4.85-5.36). 



Scutellum: Length-width ratio, 3.07(2.40-3.60) : 3.25(3.00-3.61). 



Length of body: 8.76(8.12-9.41). 



Type data. — The unlocated type of mirahilis was said to have come 

 from BrazU. Berg's types of umbonatus were reported as having 

 come from the Argentine localities of Catamarca and Tucumdn. 

 One specimen (UnivNac) in a collection of miscellaneous material is 

 labeled "Catamarca, umbonatus Berg, type." This obviously is one 

 of the original types and is here designated the lectotype. Dr. 

 Kormilev informed the author that no recognized types of this species 

 are in any other Argentine museums that he visited. 



Specimens studied. — 12 males, 13 females. 



Brazil: Campinas, Nova Teutonia, Porto Alegre, Taperina; October, 

 November. 



Peru: "Chauchamayo." 



Paraguay: Asunci6n, Colonia Nuevo Italia, Horqueta; September to Decem- 

 ber. 



Argentina: Catamarca, Tucumdn; December. 



Discussion. — Although the close resemblance between this form 

 and the common form of the southern United States led most authors 

 to consider them as one, there is sufficient difference to warrant 

 separating them. In fact, the present study also separates a geo- 

 graphically intermediate form, crassus Walker. The form of the 

 southern United States properly takes the name ciliatus Palisot de 

 Beauvois, as explained under the treatment of that species in the 

 present paper. Signoret's (1881a) synonymizing of Berg's Macroscytus 

 umbonatus is supported by the finding of the "Catamarca" type 

 mentioned above. 



For a discussion of this species in relation to others of the subgenus, 

 see comments in the introduction to this subgenus and those under 

 C. ciliatus. 



