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34 [February, 



When ready to spin up the larva finds the ground already half 

 prepared for it. The frass is out of the way, collected into one large 

 heap, whilst the contraction of the mine by the early drawing in of 

 its sides has narrowed the cavity to the requisite dimensions. All 

 therefore that remains for the larva to do is to spin a diaphragm just 

 in front of the frass heap, line the chamber, so cut off, with silk to 

 make it weather proof, and throw some strands across the front end 

 for the support and guidance of the pupa as it breaks through on the 

 emergence of the moth. Commonly the silk lining is none too abun- 

 dant, and in pulling a mine open the leafy wall and the silk lining 

 part along the same line, so that there is little appearance of a cocoon 

 as distinct from the cavity of the chamber. In mespilella and pyri- 

 vorella, however, the lining is much thicker, and instead of tearing it 

 peels off from the wall of the chamber and has all the look of a cocoon. 

 Of the greater quantity of silk these two species have at their disposal 

 we have further proof in those occasional instances where, from lying 

 across instead of along an interspace, the mine fails to contract and 

 the chamber remains over wide. If it be one of the apple species, 

 the larva uses up its supply of silk in a vain effort to draw the mine 

 in, and having none left for a special cocoon is obliged to pupate in 

 this roomy and comfortless space ; whereas mespilella or pijrivorella 

 in a like predicament spin a separate and substantial cocoon distinct 

 from the chamber. Spinicolella and cerasicolelln also construct distinct 

 cocoons (Entomologist's Record, x, 1G8-70). These two species stand 

 so plainly outside the concomiteUn group where lay the problems to be 

 solved, that they did not seem to require the same minute treatment, 

 and I neglected to note the extent to which they make themselves 

 cocoons. This deficiency Dr. Corbett's valuable note has enabled 

 me to supply, yet after all it is only a question of degree, for they 

 all make cocoons, and on identical lines, out of one end of the mine. 

 Oxynaanthx generally lines its pupal chamber with yellow silk, but 

 occasionally with white, which is the colour of the lining in the other 

 species. No other peculiarities that I can discover are shown by any 

 of the species, and in size, position and general structure there is a 

 singular uniformity about the pupal chambers, so different to what we 

 find in some other sections of the genus. The autumnal broods of 

 spinicolella and cerasicolella hibernate full-fed, those of the concomi- 

 tella group pupate immediately. The moths emerge by the under-side 

 of the leaf, with the exception of sorhi, whose rule is to come out 

 through the upper-side. 



{Tu be continued). 



