Dec. 20, 1915 Clierry and Hawthorn Sawfly Leaf Miner 523 



The technical description of each of the larval stages follows: 



First instar. — Body translucent, white, shining; only slightly wrinkled, and with 

 a green streak, due to alimentary tract, showing plainly in the abdominal segments. 

 Prolegs appear as only slight elevations. 



Head is slightly bro\N-nish, being of dark color on the outer and posterior edges; 

 mouth parts are reddish brown. The ventral side of the first thoracic segment has 

 a pair of bro^\^lish gray marks, shaped roughly like a T, %vith the cross bar running 

 longitudinally and tlie perpendicular reaching outward to a point just in front of 

 the leg. A semicircular line of the same color occurs in front of the anus and is inter- 

 rupted on tlie median line. 



Newly hatched larvae are about 1.2 mm. in length, and after feeding, the body 

 grows, reaching a length of 2.3 mm. Width of head, 0.36 to 0.42 mm.; average, 0.39 

 mm. 



Second instar. — All markings of body are more extensive than in preceding stage. 

 Dorsal side with some specimens has a broad, faint, bro\\-nish gray, transverse band 

 on the first thoracic and two spots on the second thoracic segment. The pair of marks 

 on ventral side of first thoracic segment are shaped more like inverted V 's, and between 

 them there is a large longitudinal band. The second and third segments have median 

 oval spots. Each proleg is marked by a narrow crescent on the anterior side. A 

 semicircular mark on the last segment extends over half a circle and is not interrupted 

 on the median line. 



Lengtli, 2.6 to 3 mm. Width of head, 0.4S to 0.55 mm.; average, 0.52 mm. 



Third instar. — All markings are the same as in preceding stage, but are much 

 fainter. Prolegs are more prominent; those on the first and penultimate abdominal 

 segments are small. 



Length, 3.2 to 4.3 mm. Width of head, 0.63 to 0.73 mm.; average, 0.67 mm. 



Fourth instar. — The characteristic markings in preceding stages practically- dis- 

 appear in this instar. A ring of several rows of minute papillEe surroimds the anus. 

 These probably exist in the earlier instars and escape detection because of their 

 small size. 



Length, 4.5 to 7.2 mm. Width of head, 0.8 to 0.9 mm.; average, 0.85 mm. 



Fifth instar. — This is similar to fourtli instar. There are no distinct color markings. 



Length, 6.5 to 7.5 mm. Width of head, 0.92 to 1.07 mm.; average, i mm. 



Sixth instar. — The body does not differ from that of preceding stage. The head 

 assumes a vertical position. The foiu" sutures on the dorsal side are ver%' faint. The 

 clypeus and labrum are shorter than in fifth instar. Tlie mandibles protrude promi- 

 nently and do not meet at the ends. The labium and maxillae project from beneath 

 the head to beyond the tips of the mandibles. 



Length is same as in fifth Instar or may be a trifle shorter. Width of head, 0.90 to 

 1.05 mm.; average, i mm. 



PUPA 



L'ntil color of adult begins to show, the pupa is white in all portions except the 

 eyes, which are reddish. Length about 5 mm. 



"Body [of female] black, ^vith tlie clypeus. labrum, malar space, the mandibles, 

 the first segment of the antennae, the tegulae, a narrow margin to the pronotum, and 

 the legs, for the most part, whitish. The prothorax, except the parts named, the 

 cephalic part of the mesopleiu-cs, and the pectus, rufous; the posterior femora more 

 or less shaded ^^-itll fuscous; the head smooth with anteimal furrows interrupted on 

 the middle of the face; tlie furrows surroimding the postocellar area deep and dis- 

 tinct, the vertical furrows not reaching the occiput; tlie median ocellus placed on a 

 flat depression; a pit above the antennal socket; the median fovea minute but dis- 



