Notes on North American Species of Ncpticxila. 



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^I. Mine collected August 18th. 



Length of mine, Aug. 18th 5 cm. 



(a) Increase, Aug. 18-19 3 cm. 



(b) Increase, Aug. 19-20 3 cm. 



(c) Increase, Aug. 20-24 .2 cm. 



(The greater part of this time was probably taken in moulting.) 



(d) Increase, Aug. 24-25 1-2 cm. 



(e) Increase, Aug. 25-26 1.3 cm. 



( f ) Increase, Aug. 26-27 2 cm. 



(g) Increase, Aug. 27-29 cm. 



(Representing another moult.) 



(h) Increase, Aug. 29-30 2.5 cm. 



( i) Increase, Aug. 30-31 2.8 cm. 



( j ) Increase, Aug. 31-Sept. 1 2.7 cm. 



(k) Increase, Sept. 1-2 9 cm. 



On Sept. 2d the larva left the mine to pupate. 



II. Mine collected September 1st. 



Length of mine, Sept. 1st 3.9 cm. 



(g') Increase, Sept. 1-2 cm. 



(Corresponding to second moulting period noted above.) 



Increase, Sept. 2-3 8 cm. 



(h') Increase, Sept. 3-4 1.1 cm. 



(i') Increase, Sept. 4-6 3.6cm. 



(Xo observation made on September 5th.) 



(j') Increase, Sept. 6-7 2.9cm. 



(k') Increase, Sept. 7-8 1.2 cm. 



The larva left the mine to pupate on Sept. 8th. 



III. Mine collected September 1st. 



Length of mine, Sept. 1st 4.9 cm. 



(h") Increase, Sept. 1-2 1.5 cm. 



( i" ) Increase, Sept. 2-3 2.4 cm. 



( j") Increase, Sept. 3-4 2.7 cm. 



(k") Increase, Sept. 4-5 2.4 cm. 



The larva left the mine to pupate on Sept. 5th. 



19 



