401 



Silaon blaisdelli n. sp. 



Female : Length 3.5 mm. ; wing 2.5 mm. 



Nervulus interstitial with the basal nervurc, first recurrent nervure 

 received by the first cubital cell. 



Black ; mandibles more or less piceous at apex ; interrupted line on 

 collar, tubercles, spot on tubercles, tegulae, spot on apex of front and 

 middle tibiae behind, stripe on tibiae outwardly, calcaria, and stripe 

 on metanotum yellowish-white ; margins of tergites and sternites pale 

 testaceous. Body with appressed silvery pubescence, more conspicu- 

 ous on sides of face, and on the margins of the tergites laterally 

 Clypeus shining not carinate, produced into a short rounded process 

 in the middle, front below with a tectiform ridge ; gibbosity of front 

 not impressed ; eyes but little divergent below ; ocelli in an olituse 

 triangle ; the posterior ocelli in front of the summit of the eyes, about 

 one half as far from the eye margin as from each other. 



Face, front, vertex, occiput, collar, mesoscutum, scutellum and meta- 

 notum finely, closely and distinctly punctate, the metanotum more 

 finely so ; mesopleura with the surface sculpture similar in general but 

 somewhat concealed by the pubescence, above the impressed pit on the 

 mesepimeron is an ill-defined, glabrous shining spot with the surface 

 microscopically tessellate. Propodeum with the basal area well defined 

 by a U-shaped raised line, basally are some weak radiating striae not 

 one-fourth the length of the area, apically the rugosity of the surface 

 is transverse ; sides of propodeum finely longitudinally striolate ; fovea of 

 posterior face shallow, the parallel transverse ridges feeble but numer- 

 ous and reaching well toward the sides. 



Wings subhyaline, iridescent, the venation brownish. The petiole 

 of the second cubital cell short, not more than a fourth the length of 

 the sides of the cell, the cell triangular. 



Abdomen shining, finely, discretely punctate. 



Described from a single female collected at San Diego, 

 California, March 29, 1891 (Dr. F. E. Blaisdell). Type in 

 tlie author's collection. 



Similar to roinreri. From rohirerl it differs bv the well- 

 detined i)ropodeal area and longer propodeum. The basal area 

 is V-shaped in rolurcri. Parvus (of which the female is un- 

 described) is described as having the radial cell not appendi- 

 eulate while it is distinctly so in blaisdelli. The basal area 

 of the pro]iodeum of parvus is described as triangular while it 

 is distinctly rounded behind in hlaisdelli. Otherwise from the 

 description the species are very near each other. 



