28 NORTH AMERICAN BLATTIDAE 



ventro-caudal margin unarmed except for a shorter distal spine. 

 Median and caudal femora with ventral margins armed with irreg- 

 ularly placed, moderately strong spines and distad with a single 

 spine. Tarsal joints elongate; first three without pulvilli; fourth 

 small, quadrate, with pulvillus occupying all of ventral surface. 

 Arolia present, distinct but small. 



Euthlastoblatta abortiva (Caudell) (Plate I, figures i to 8.) 



1904. Anaplecta abortiva Caudell, Mus. Brooklyn Inst. Arts and Sci., Sci. Bull.- 



i, p. 105. [ 9 , Esperanza Ranch near Brownsville, Texas.] 

 1913. PhyUodromica abortiva Caudell, Proc. U. S. Nat. Mus., xliv, p. 600, fig. 9, 



p. 603. (Same specimen.) 



At first glance the color pattern of this beautiful species suggests 

 that of certain species of Pseiidomops; it is, however, on closer 

 examination found to be of an entirely different type. 



The strongly transverse supra-anal plate, weaker spines of the 

 femoral margins than is usual in the present subfamily and re- 

 duced tegmina of the female, led Caudell, who had that sex alone 

 before him, to consider the species a member of the Ectobiinae, 

 as shown in the above references. 



The species is very distinct from any of the other forms here 

 treated. 



As the male of this species was previously unknown, we here 

 describe a topotypic male, a specimen secured with the type. 



Description of Male. — (Esperanza Ranch near Brownsville, Texas.) Size small, 

 form moderately slender. Interocular space broad, slightly narrower than the 

 broad interantennal space, ocellar spots distinct but irregular. Maxillary palpi 

 elongate, with distal joint enlarging decidedly. Pronotum weakly convex, showing 

 a slight latero-caudal discal flattening; outline elliptical, showing a distinct caudal 

 truncation, point of greatest width meso-caudad. Tegmina and wings fully devel- 

 oped, extremely delicate in structure (see generic description). Tegmina with 

 margins of mesal third parallel; apex broadly rounded; mesal field occupying but 

 one-third of costal margin. Supra-anal plate very strongly transverse; dorsal sur- 

 face weakly concave; very weakly {produced between cerci, with free margin trans- 

 verse, showing a weak convexity and a very feeble median emargination. Within 

 the anal chamber, mcso-ventrad, from beneath two large, lateral, chitinous plates, 

 a very wide subchitinous structure, with parts convergent, is produced caudad, with 

 its short, stout, chitinous, distal portion armed above with very thickly set micro- 

 scopic spines and terminating in a fringe of closely set, curved, spiniform hairs, 

 arranged in a whorl. (Plate I, figs. 4 and 5.) The apex of this remarkable process 

 is consequently flat and normally is carried resting just within the median eniar- 



