300 THE CANADIAN ENTOMOLOGIST. 



the hind legs, more or less honey-yellow. In the hind legs, ihe base of 

 the coxae, the extreme tips of the femora and the tarsi are more or less 

 fuscous. Eighth, the veins on the costa are scarcely whitish, and only 

 the extreme base of the stigma is whitish. Length of male .10 to .17 

 inch. 



Description of Euura S. nodus as compared with Euura S. ovum 

 (Walsh). "Imago. — Euura S. nodus, n. sp. — Male differs from male of 

 Euura S. ovum as follows : First, the pale colour is bright honey-yellow, 

 not greenish-white throughout; that is, both in antennae, body and legs. 

 Second, the black spot enclosing the ocelli is larger, and confiuent with 

 the eye for its entire length, leaving no orbit between them. Third, the 

 venter dried is honey-yellow on the terminal three or four joints, and in the 

 middle only of one or two more. Basal plates black, as in Euura S. 

 gemma. When recent, the venter was noticed as being greenish, and the 

 legs are pale fulvous. Fourth, the legs dried are honey-yellow, immacu- 

 late, except the extreme tarsal tips. Fifth, the basal one-half of the stigma 

 is whitish, as in Euura S. ovum, female. Length, male .16 to .17 inch ; 

 front wing of male .17 to .18 inch. Two males, female unknown." 



The following is a description of the females which I have reared in 

 large numbers from the galls : 



Euura S. Jiodus, female. — Shining honey-yellow. Length, .22 to .25 

 in. Head : Black spot enclosing the ocelli usually small, and not 

 confluent with the eyes, palpi and tips of m.andibles black, otherwise 

 yellow. Anlennse : Last four joints of a more or less rufous tinge ; basal 

 joints black, 3rd, 4th and 5th joints subequal, very gradually shorter to 

 tip, ninth joint probably a trifle longer than eighth. Thorax with an 

 oblong spot extending from the collar two-thirds of the way to the hind 

 angle of lobe of the mesonotum. Metathorax, also sometimes pleura 

 and pectus, black. There is a great variation here, and sometimes pleura 

 and pectus are entirely yellow. Basal plates black. Abdomen yellow, 

 with the exception of the sheath of the ovipositor, and part of the first 

 segment, which are black. Legs honey-yellow, with tarsal claws blackish. 

 Wings hyaline, veins black except costal margin vein and base of stigma, 

 which are whitish. 



The general appearance of Euura S. nodus and Euura S. ovum are 

 the same. The latter is, however, much smaller, and the females of a 

 darker colour. 



Quite a number of Euura S. ovum galls were collected, but only a 

 very itw brought to maturity any of the Saw-flies, In fact, very few of 



