210 Transactions. 



eighth abdominal segment ; head pale yellowish-brown, sutures and mouth- 

 parts reddish and darker. Cephalic ganglia not noticeable ; ventral chain 

 not noticeable ; no conspicuous markings ; the thin brown lateral lines on 

 the dorsum of the last segment are situated so far laterally as to be almost 

 out of sight when the larva is viewed dorsally. Surface of body covered 

 with a very minute pile. Setae inconspicuous ; main setae about half as 

 long as their respective segments. The larva mines dorsum uppermost. 

 It is a frequent prey to minute hymenopterous parasites, the pupal 

 duration of which is about fifteen days. 



The Cocoon. 



The cocoon is constructed within the blotch close against its outer margin, 

 where the larva, previous to the construction of the cocoon, cut a slit-like 

 opening through the lower cuticle ; this slit may be 4 mm. to 5 mm. in 

 length, but is very inconspicuous. The presence of the cocoon is made 

 known by this slit and by a slight bulging of the under-cuticle where it 

 is situated. It is rarely noticeable from above ; though sometimes the 

 cuticle covering it may become slightly lighter in shade where the cocoon 

 is attached. The cocoon can easily be found by holding the mine against 

 the light. It is attached to both the roof and the floor of the mine, but 

 more firmly to this latter, from which it is almost impossible to detach it 

 completely. When seen against the light the anterior third is lighter in 

 colour than the rest, as the pupa is situated farther back and the structure 

 of the cocoon is here somewhat less dense. At the anterior end of the cocoon 

 its floor and roof can easily be split apart ; this is the prepared outlet for 

 the pupa. The cocoon is oval in shape, broader at its anterior end, 4-5 mm. 

 by 2 mm., flattened top and bottom 1 mm. The silk on the outside is 

 pale-yellowish and compact, and within this is an inner cocoon of white 

 silk which also has its prepared anterior outlet. When the imago is 

 ready to emerge the pupa is thrust out the anterior end of the cocoon and 

 through the slit in the under-cuticle, the anal segments being retained 

 within the cocoon. The presence or absence of the empty puparium indi- 

 cates the state of affairs within the cocoon. Emergence takes place on the 

 under-surface of the leaf. 



The Pupa. 



Ventral view : Outline oval ; front bluntly rounded ; a slight incisura 

 between front and base of antenna, this latter slightly prominent. The 

 last six abdominal segments occupy the lower third of the lateral profile. 

 Spiracles prominent, especially on 8. Last segment rounded with a slight 

 caudal notch ; genital opening showing on the ventral surface. The eye 

 is covered over its cephalo-lateral third by the base of the antenna, and 

 slightly caudad by the maxillary palpus. Fronto-clypeal suture not very 

 distinct. Maxillary palpus well developed ; reaching from the antenna 

 laterad to the labrum, of which it sometimes falls slightly short ; broadest 

 at its base against the antenna. Labial palpi narrow, slightly bulbous 

 in their caudal half ; extend caudad farther than the maxillae. Maxilla 

 broad cephalad ; occupies the mesial half of the maxillary palpus ; pointed 

 caudad. First legs fairly short and stout, broader cephalad ; extend to 

 just below the first coxae ; the femur occupies a small narrow strip 

 between their upper half and the maxilla, and abuts on the maxillary palpus 

 cephalad. Second legs may not reach so far cephalad as the maxillary 

 palpus, but extend caudad as far as the junction of the fourth and fifth 

 abdominal segments. From beneath them, and extending farther caudad 



