27 



DESCRIPTION OF THE SPECIES. 



Tlie female sawfy may be recognized with the aid of the accompany- 

 ing- illustrations — figure T, «, representing the insect with wangs 

 expanded and three times the natural size, figure 8, ^, showing the 

 same with wings folded and natural size, on a violet leaf — and Cresson's 

 translation of Provancher's description (Tr. Am. Ent. Soc, Vol. VIII, 

 p. 38): 



" 9. — Length, 0.22 inch; black; head transverse, angular, as broad as the thorax, 

 punctured, with a furrow on each side behind the ocelli; antennaj moderate; palpi, 

 tegute, legs, with trochanters and tips of the coxae, dull yellowish-white; posterior 

 femora except base, tips of their tibi;e, with their tarsi, black or deep brown; 

 abdomen entirely black, slmrt and stout; wings hyaline, nervures brown, the costa 

 and stigma deep brown." 



The flies reared at Wash- 

 ington difl'er slightly from 

 the above description, as did 

 those reared by Dr. Dyar, in 

 .having the fore and middle 

 tarsi darker toward the 

 apex. Some of the veins and 

 stigma are very dark brown 

 and others are black. 



Measurement of the mate- 

 rial at hand gives an average 

 of 12.5™" wing expanse and 

 6.5"^™ total length of body. 



THE EGG AND OVIPOSITION. 



The individual fly which 

 issued April IS was placed 

 in a jar with a potted violet 

 plant, and was soon running 

 about on the leaves with 



vibrating antennae and active jaws and ligula, apparently feeding freely 

 and making frequent attempts to insert her ovipositor in the leaves. 

 This she was unable to accomplish with many of the older leaves, 

 neai'h' all of the eggs found having been inserted in the tenderer leaf- 

 age. Oviposition and the subsequent escape of the 3'oung larva from 

 the place of deposit is not unlike that of the common pear slug, Erlo- 

 caiiipoidex I'lmaclna Retz. , with the process reversed, the ^^^ being 

 inserted from the upp'er side of the leaf and the larva escaping on the 

 under surface. The ovipositor is thrust through from above to the 

 lower epidermis, which is left intact, the nidus thus formed with its 

 contained ^^'^ appearing as a blister on the lower surface. 



Fk;. 7. — Einpliijtus canadensis — «, female savvfly; b, larva; 

 c, abdominal segments of larva from above; d, pupa; e, 

 cocoon — all except c four times enlarged (original). 



