THE CRANE-FLIES OF NEW YORK PART II 709 



are usually deposited in series along and just within the margin of the serrate, palmately- 

 lobed leaf. They are found in groups of one or more, all arranged parallel to one another 

 and with their long axes perpendicular, or nearly so, to the margin of the leaf. The eggs 

 are only partly hidden beneath the epidermis, being exposed dorsally, the margins of the 

 slit overlapping the egg laterally and, to a lesser degree, both anteriorly and posteriorly. 

 This arrangement of the eggs in series gives to the leaf margin a somewhat beaded appearance. 

 When the eggs are older, the leaf margin turns brown and the presence of the eggs is readily 

 detected. In ovipositing, the female rests on the under side of the leaf, with the tip of the 

 abdomen directed toward the leaf edge. The abdomen is slightly flexed ventrally, and the 

 margin of the leaf is held between the bifurcated valves of the ovipositor, which is applied 

 to the upper surface of the leaf, while the paired cutting valves, with their blades, are applied 

 against the under surface. These blades are then moved to and fro, cutting a slit in the 

 epidermis. The eggs are then deposited. In no case do the eggs actually touch one another 

 on the leaf. In the breeding cages females lay their eggs indiscriminately on both the upper 

 and the lower surface of the leaves. In some cases, when a leaf has been eaten earlier in 

 the season by larvae, the female will deposit her eggs along the ragged edge of this damaged 

 part. 



The indoor duration of the egg stage is from fourteen to eighteen days, but in the field 

 as long a period as three weeks may be required. When first deposited the egg is translucent, 

 grayish white, and spindle-shaped, with the chorion unornamented, and measures on an 

 average 0.84 by 0.303 millimeter. 



The larva requires about three hours to emerge from the egg. The chorion of the egg 

 splits longitudinally down the mid-dorsal line, the slit extending almost half the length of 

 the egg. In emerging, the almost transparent, grayish white larva utilizes the body tubercles 

 as levers in freeing itself from the eggshell. As soon as it is freed from the shell, the newly 

 hatched larva begins to feed on the leaf tissue of the host plant. 



The first-stage larvae are grayish white in color, are translucent, and measure 1.19 by 

 0.37 millimeter in size. They feed on both the upper and the lower surface of the leaf, 

 burrowing thru the epidermal layer with their mandibles and feeding on the parenchymatous 

 tissue within. The young larvae are very sluggish and are not readily disturbed when 

 feeding, the mandibles being firmly embedded in the leaf tissue. While engaged in feeding 

 they assume various positions on the leaf surface. At the end of nine days the larvae have 

 increased in length to 5.84 millimeters, and show all the characteristic behavior of the full- 

 grown larvae. Growth is very slow, and before the first molt the larvae become covered 

 with particles of their excrement, which adheres readily to the skin. The first larval molt 

 occurs after a period of from eighteen to twenty-one clays; in some cases, however, it does 

 not occur until five or six weeks have elapsed. 



The second-stage larvae gradually assume a leaf-green color as they continue to feed. 

 Toward the end of July, coincident with the dying-off of their food plant, the larvae, which 

 have now reached a length of from 8.32 to 9 millimeters, become quiescent and cease to 

 feed. Feeding and movement gradually cease completely and the larvae remain clinging 

 motionless to the leaves. As the leaves wither, the larvae drop off, and, in some cases, 

 attach themselves to the stems; under natural conditions, however, they usually fall among 

 the dead leaves on the ground and under these they pass the whiter in a dormant condition. 

 Many of these larvae match the brown color of the dead leaves, but some of them retain 

 their leaf-green tint. 



The overwintering larvae first show signs of activity in March of the following spring, 

 when Trautvetteria grandis sends up its new shoots. Growth then proceeds rapidly until 

 pupation in the middle of May. There seems to be one molt before hibernation and two 

 after, the last being the casting of the larval skin, previous to pupation. The fully grown 

 larvae measure 17 millimeters. They are invariably found on the upper surface of the leaf, 

 and in the spring are actively engaged in feeding. On a fresh leaf the larvae usually begin 

 by skeletonizing it, leaving the lower epidermis intact. Later on, however, large holes may 

 be eaten completely thru the leaf. The fully grown larvae, and to a somewhat lesser degree 

 the younger larvae, progress by a looping motion, which may be aptly compared to that 



