600 The Philippine Journal of Science 1923 



Diodontus ajaxellus sp. nov. 



Apparently somewhat like Psen ornatus Ritsema but differs 

 in some color markings and in venation. 



Male.— Length, 7 millimeters. Slender. Anterior margin of 

 clypeus with two small, triangularly shaped teeth medianly; 

 transverse ridge below antennae strong, and joining the equally 

 strong frontal ridge medianly; Irons and vertex shining; ocelli 

 in nearly an equilateral triangle; postocellar line slightly less 

 than ocellocular line; antenna? as long as head and thorax, 

 joints 6 to 12 rounded out beneath, third joint subequal with 

 fourth; pronotum carinate anteriorly, lateral anterior angles 

 sharp but not dentate; scutum polished and with a few punc- 

 tures; notauli indicated anteriorly; dorsal surface of propodeum 

 polished, basal area triangular in outline and crossed by strong 

 rugse which are more widely separated medianly ; posterior face 

 of propodeum coarsely reticulate, the median channel deep ; 

 mesepisternum polished, the suture foveolate; petiole gently 

 curved, cylindrical, fully as long as hind femur, not very sharply 

 separated from rest of tergite; gaster polished; first recurrent 

 received by first cubital cell close to first intercubitus ; second 

 recurrent bisinuate, received by third cubital a distance equal 

 to half the length of second intercubitus from base of cell ; sec- 

 ond intercubitus perpendicular; second cubital cell one-third 

 longer below. Head and thorax black ; mandibles and scape yel- 

 low; flagellum, from the basal joints, testaceous beneath; dorsal 

 part of pronotum, three spots on mesepisternum (the lower one 

 smallest), spot below hind wings, scutum except three broad 

 lines, scutellum, metanotum, and posterior face of propodeum 

 (except median channel) yellow; four anterior legs and hind 

 coxae yellow ; hind legs below coxae testaceous ; abdomen rufous, 

 base of petiole yellowish; head with the usual pale pubescence; 

 wings hyaline, venation pale brown. 

 Type locality. — Kolambugan, Mindanao. 

 Described from one male received from C. F. Baker. 

 Type.— Catalogue No. 25045, United States National Museum. 



Diodontus esuchus sp. nov. 



Male.— Length, 8 millimeters. Close to Diodontus ajaxellus 

 sp. nov., from which it differs as follows: More robust; third 

 antennal joint distinctly longer than fourth; petiole strongly 

 curved ; first recurrent received by first cubital a distance equal 

 to about one-third the length of first intercubitus from end of 

 cell ; second cubital cell about one-fourth longer below (due to 



