1917.] NATURAL SCIENCES OF PHILADELPHIA. 247 



ANCISTROGASTRIN.E. 



LITOCOSMIA" new genus. 



This genus agrees with Osteulcus alone, of the genera of the present 

 subfamily, in the male penultimate ventral abdominal segment 

 lacking projecting processes, but differs from that genus in the form 

 of this segment, the tegmina which are not keeled beyond the shoul- 

 ders and in having the seventh dorsal abdominal segment alone 

 specialized laterad, not considering the stink glands.-^ The abdomen, 

 with greatest width mesad, gives a superficial resemblance to Mixo- 

 cosmia. The evenly and not strongly arcuate forceps suggest the 

 type found in some species of Paracosmia, but are more simple. 



Genotype. — Litocosmia roraimce new species. 



Generic Characters. — Head feebly depressed meso-caudad. First 

 antennal joint equal to coml^ined length of second, third and fourth 

 joints; fourth joint distinctly longer than third. Pronotum sub- 

 quadrate; cephalic margin transverse, with lateral angles rather 

 sharply rectangulate, caudal margin convex. Tegmina keeled only 

 at shoulders. Abdomen gradually widening to seventh dorsal 

 segment, thence gradually narrowing; stink glands of third segment 

 well developed, of fourth segment strongly developed, tubular; 

 seventh segment with a dorso-lateral oblique, rounded ridge on each 

 side, ascending cephalad; other segments simple. Pygidium minute, 

 simple. Forceps not complex in structure. Penultimate ventral 

 abdominal segment rectangular, disto-lateral angles broadly rounded, 

 distal margin transverse. Limbs- elongate and slender; caudal 

 metatarsus slightly longer than third tarsal joint, its ventral surface 

 and that of second tarsal joint, hairy. 



We believe the correct linear position of this genus to be after 

 Sarakas and before Mixocosmia, then Paracosmia. 

 Litocosmia roraimae new species. P!. XVI, figs. 10, 11. 



Type: cf ; Ireng River to Roraima, Brazil. August 18, 1911. 

 (Crampton) [American Museum of Natural History.] 



Size medium, form elongate and slender, with greatest abdominal 



^^ From /i~'i = pimple. 



'-' We are not as certain as we would like to be that the species, or at least the 

 genotype, of Burr's genus Sarakas, will not also be found to have a simple male 

 penultimate ventral abdominal segment. This segment is not described in the 

 original descriptions. The genus is assigned to the opposite categor.v in Bui-r's 

 key in the Genera Inseclorum, but we have already found this same key to be 

 elsewhere misleading. From the description of the genotype, Sarakas devians 

 (Dohrn), it appears that Litocosmia is at least separable by the dilated abdomen^ 

 with lateral portions of sixth and eighth dorsal segments unspecialized, and 

 the much more simple type of forceps. 



