378 STUDIES IN THE ISCHNOPTERITES (oRTHOPTERA) 



the mesal area between these ridges subchitinous. Dorsal abdominal seg- 

 ments all with latero-caudai angles similarly acute-angu'.ate produced to 

 sixth segment; sixth segment narrowly visible, except laterad where the latero- 

 caudai angles are very strongly produced, with rounded apex extending beyond 

 median portion of eighth segment, and external margin curled over; seventh 

 segment with apparent portion nearly as narrow as sixth but not produced 

 laterad; eighth segment more broadly visible, with caudal margin showing a 

 small triangular production above each cercus, and strongly concave mesad 

 between these. Supra-anal plate weakly produced and weakly bilo])ate 

 between cerci, and fringed distad with fine hairs, the structure showing only 

 traces of a subchitinous condition along the distal margin. Subgeiiital plate 

 weakly convex, narrowly but strongly reflexed along the sinistral i)ortion of 

 its free margin, which is heavily chitinous and armed with three widely spaced, 

 stout, short dorsal teeth, this part extending to beneath the sinistro-distal 

 curve of the supra-anal plate, thence the free chitinous margin is weakly 

 oblique, nearly transverse, to beneath the dextral style, but a narrow cartila- 

 ginous mantle covered with numerous minute hairs occupies this margin, the re- 

 maining l:)rief dextral portion of the margin is straight, longitudinal to the base 

 of the plate, in greater part occupied by the cartilaginous integument connect- 

 ing the stout chitinous base of the dextral style with the plate. From within 

 at the base of the plate, at its sinistral margin, an elongate, stout but tapering, 

 chitinous arm is weakly curved dextrad, extending to the distal extremity of 

 the heavy, sinistral, marginal portion of the plate; this greatly speciaUzed 

 sinistral style is armed on its outer face at the extremity of its stout proximal 

 third with a short stout tooth, the distal portion of the style is strongly curved 

 to its acute apex. Dextrad, beneath the cercus, from the inner surface of the 

 sul)genital plate at its dextral margin, springs another heavier, elongate, chiti- 

 nous arm, stout at its base, liut slightly beyond bearing two elongate, slender, 

 adjacent, dorsal, membranous cylindrical processes, which spring from a brief 

 chitinous base and have acute chitinous apices, from this point the main 

 shaft is more slender, slightly tapering and curving weakly caudad to the apex, 

 which bears two minute, chitinous teeth and nearly reaches the apex of the 

 sinistral arm. These arms (highly speciahzed styles) are mobile, connected 

 with the subgenital plate at their bases by a cartilaginous integument; when 

 at rest they lie along the inner surface of the subgenital plate at its free mar- 

 gin. "* 



The females before us agree closely with Griffini's description. 

 We would note the following features. 



Characters of 9 . — (On S. S. Tenadores, en route.) Similar to male, but with 

 much shorter tegmina and wings.''" Dorsal abdominal segments of the general 

 character of those of carrikeri, but all showing a slightly greater production. 

 Supra-anal plate convex produced between cerci, showing hardly a trace of 



"•^ Thus, in dried material, their form can probably seldom be seen without 

 relaxing. 



''"The ulnar vein of the wings has 1 to 2 incoiiipietc and 2 to W complete 

 rami in the two females before us. 



