12 G Canadian Arctic Expedition, 1913-18 



antennae slender, the third segment shorter than either the fourth or fifth, the 

 fifth shorter than the fourth, the surface finely punctured and setaceous; the pro- 

 notum and the median and lateral lobes of the mesonotum finely densely granular; 

 the mesoseutellum and mesopostscutellum polished; the mesopleura finely 

 densely granular, the mesosternum and metapleura polished; the wings hyaline, 

 the veins and stigma pale: the claws deeply cleft, the inner ray nearly as long as 

 the outer; the abdomen faintly granular, polished; the saw-guides broad and 

 stout, the dorsal margin straight, the ventral margin broadly convex, the con- 

 vexity continued to the dorsal margin, forming an oblique bluntly pointed distal 

 end, the distal end and the ventral margin setaceous; color black with the 

 following parts yellowish: the posterior and outer orbits, the collar broadly, 

 the leiiuhe. a broad V-shaped band covering the parapsidial furrows, the cephalic 

 half of the mesopostscutellum and continuous with a similar spot on each axila, 

 a large triangular spot on the mesopleura, the legs except the trochanters in 

 part and the proximal portion of the caudal surface of the femora more or less 

 and the tarsi, the ventral aspect of the abdomen, the saw-guides, and the two 

 caudal terga. Length, 6 mm. 



Bernard harbour, Northwest Territories, July 15, 1915. Specimen No. 

 1253. 



This species resembles pomum Walsh. The punctured head, the shallow 

 emargination of the clypeus, and the general topography of the head will serve 

 to differentiate it. 



The collection contained specimens of the galls of the following from which 

 no adults were secured: 



Breeding Record: The larvae described below were collected on bushy 

 willow (Salix Richardsonii) on Herschel island, end of July, 1916. The portions 

 of the plant enclosed with the larvae in alcohol were the ends of the branches 

 bearing the seed pods and in each case had been mined by a larva. This was 

 considered at first as an indication that it was a species of Euura. It may be 

 this or it may be the larva of a species of Pontania that has completed its feeding 

 and has left its gall and is boring into the seed pod to make a place for pupation. 



LARVA. Body white, shading to brownish, with a portion of the head 

 and the articulations of the segments of the legs brownish; ocularium round and 

 black, the ocellus situated in its center; antennae convex oval area near the 

 ventral margin of the ocularia, limited by a brownish line and its surface bearing 

 eight minute brownish areas; head white with minute, round, inconspicuous 

 spots on the dorsal half, forming a fuscous spot on the dorsal half of the front; 

 mandibles distinctly dentate; spinneret prominent, the distal end bluntly 

 rounded; microthorax linear, white; thorax and abdomen with some of the 

 annulets swollen and the summit of the swollen area slightly fuscous and with 

 minute, uncoloun-d spots hearing setae; prothorax with three annulets, the first 

 and third inconspicuous, the second bearing three setae on each side of the 

 meson, the spiracular area large and swollen and bearing two setae, the pedal 

 area swollen and indistinctly separated from the spiracular area; mesothorax 

 and metathorax with four annulets, the first short and swollen, the second and 

 third subequal in length, the mesal portion of the second slightly depressed, 

 the mesal portion of the third swollen and separated from each lateral portion, 

 the lateral portions of the second annulet bearing two seta' and of the third 

 three sehe, the spiracular areas large and each bearing about three inconspicuous 

 >eta>, the pedal areas distinctly marked and swollen, setae inconspicuous; 

 abdominal segments one to eight with four annulets, the first small, the second 

 and third large and swollen and with distinctly elevated lighter coloured mesal 

 creeping ridges, the lateral portions of each bearing about two setae; spiracular 

 are;is swollen and bearing about two setae and distinctly separated from the 

 swollen pedal areas bearing two or three- setae; annulets indistinct on the ninth 

 and tenth segments; setae of the tenth segment fairly numerous and without 

 definite arrangement; prolegs long, cylindrical, and typical in form; spiracles 



