446 Transactions. 



limits of the leaf in which it is contained ; in small leaveti it becomes 

 incorporated in and obliterated by the blotch — so much so that no sign 

 of any gallery can be found. It usually follows the midrib or margin of 

 the leaf along its greater extent, sometimes being deflected by the coarser 

 veins ; in this manner its course may be slightly tortuous, but rarely - 

 markedly so. The midrib forms an impassable barrier except at its upper end. 

 The irregular blotch may cover an expanse of about 1| square inches. Colour 

 of the mine conspicuously' white or light green, sometimes discoloured a 

 bright reddish-brown, but patchy in character. That part of the leaf 

 covering the blotch is, in fleshy leaves, more or less mottled in shades of 

 green according to the closeness of the mine to the outer cuticle. Frass 

 exceedingly scanty, black, finely granular, occupies a thin line near one 

 side of the gallery, sometimes abruptly changing from one side to the other. 

 After the first moult the granules are- irregularly scattered over the floor 

 of the mine. Leaves are seldom found containing more than two mines. 

 The blotch is almost invariably boimded on the outside by the margin of 

 the leaf. 



The Larva. 



The first moult occurs about 6 cm. or 7 cm. from the commencement 

 of the gallery. Structural details of the larva are reserved for a future 

 paper. 



The Cocoon. 



The cocoon is a delicate structure of white sUk within the blotch part 

 of the mine. It is oval in outline, and compressed above and below. 

 Average .size 10 mm. by 4 mm. The head end may be slightly broader 

 than the other. It is not conspicuous from the exterior, a very slight 

 puckering of the leaf aroimd its circumference, and a small degree of 

 fuUness in that part, alone betraying its presence. On holding the leaf 

 up against the light the pupa may be distinguished by its shadow, and 

 its health determined by the vigour of its movements when so disturbed. 

 There is no evidence on the exterior of any prepared place for exit. 



The Pupa. 



As seen from the side the pupal outline is rounded at the head (except 

 for the cephalic plate), and more prominent dorsally. There is a slight 

 stricture in the dorsal outline at the pro thorax, otherwise the dorsal 

 outline is abiiost straight. Ventrally there is a fairly deep stricture 

 between the eye and the first leg, occupied by the maxillae. Ventral 

 profile somewhat rounded, the body becoming slightly attenuated towards 

 the caudal extremity. A ventral view of the pupa shows the cephalic 

 plate occupying about one-third of the width of the head between the 

 antennae ; the outline from its base to the antenna is almost straight ; 

 the greater diameter is opposite the caudal extremity of the labial palpi, 

 the body from here becoming gradually attenuated caudally. 



The head : Cephalic plate well developed into a long, slender spear- 

 point, about one and a half times the length of the eye, twice as long as 

 its ventro-dorsal diameter at its base, projected forward at an angle of 

 about 45° to the long axis of the pupa ; the pair of frontal tubercles 

 bear long and slender setae, slightly longer than the cephalic plate ; no 

 trace of lateral cornua. Eyes large, prominent, only slightly covered by 

 base of antenna. Labrum situated between eyes at about their middle. 

 Mandibles small but encroaching caudally upon the labrum. Labial palpi 



