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DESCRIPTIVE DETAILS. 



DESCRIPTIONS AND LIFE-HISTORY. 



Appearance in the -Spring. — The beetles which have lived over 

 winter come forth from their retreats during the latter part of 

 April or early in May. In the vicinity of Syracuse they are 

 usually first seen from the first to the tenth of May. As pre- 

 viously stated the beetles feed voraciously on the new growth, 

 preferring the tender bark, but also feeding upon the leaves, and 

 frequently devouring the youag shoots before they have fairly 

 started. ^ 



The egg. — Egg-laying begins about the tenth to the fifteenth of 

 May and may continue for a week or more. The eggs are 

 deposited in groups, usually on the under surface of the willow 

 leaves, but they were frequently found upon blades of grass or 

 leaves of weeds growing in the willow rows. Each egg is firmly 

 fastened on end to the leaf and usually in a slightly slanting posi- 

 tion as shown at Plate III, on the left of fig. i. These groups 

 vary in the number of eggs contained. In about fifteen examined 

 the number varied from 25 to 52. The average number is about 45. 



The eggs are light lemon-yellow in color turning to a deep 

 salmon just before hatching. They are' elongate-oval in outline 

 and vary in size from 1.35 mm. by 0.63 mm. to 1.47 mm. by 

 0.84 mm. The shell is smooth, thick and leathery. 



Period of incubation. — The period of incubation is usually 

 from ten days to two weeks. This was the period for 1894, 1895 

 and 1896. Last spring was an exception as few of the eggs 

 hatched within twenty days. 



The larva. — When first hatched the larvae measure from 1.05 

 mm. to I. II mm. in length. The diameter of the head is 0.6 

 mm. and that of the body 0.54 mm. on the anterior half taper- 

 ing to 0.21 mm. at the last abdominal segment. The entire body 

 is black or very dark brown. When full grown they measure, on 

 an average, about 8 mm. in length. The width of the head is 0.75 



