208 THE MONTHLY BULLETIN. 



5 layers. The outer layer is the whitish network of threads which may 

 or may not turn brownish as they become older. The closely woven 

 layers underneath this give the color to the cocoon, the very inside 

 layer having little of the brownish color which may be due to lack of 

 contact with the atmosphere. The cocoon varies in shape with the 

 surface, which is in contact with it, and the shape of the cocoon of the 

 codling moth. The upper and loM'er sides and one end are, as a rule, 

 flat, although this is not constant by any means. The angles are made 



Fig. 69. — Cios.s-.section of codling moth cocoon 

 showing' remains of codling moth larva and pupa of 

 CaUiephialtes in it.s cocoon. Gretaly enlarged. 

 (Original.) 



of nearly doulile the number of layers of which the sides are made up, 

 and are very stiff. The flat end is usually of thicker material than 

 tlie sides, consisting of, usually, five distinct layers, while the top and 

 bottom have only three. The average cocoon approaches a point at 

 the opposite end. The greatest diameter is transverse and slightly to 

 one side of the center. The lateral sides of the cocoon are more or less 

 rounded. 



The larva, at a temperature of 61° or 62° F. re(|uires from four to 

 five days to complete the cocoon. The larva remains in this enclosure 

 from three to six days before the prepupal stage is reached. The co- 

 coons average about 5.7 mm. in width and 9.9 mm. in length. 



The Prepupal Larva. (Figure 70.) From twelve to ninety-six 

 hours after the larva voids the meconium, constrictions appear in the 

 integument, the reddish eye spots begin to appear on the first body 

 segment and the prepupal stage is reached in from twelve to twenty- 

 four hours. The constrictions are not visible in the head and first body 

 segments or on the ventral portions of the first two thoracic segments. 

 On the third thoracic segment, however, the constrictions are very plain. 

 The color of the prepupa is whitish. The eye spots increase in density 

 as the stage draws to a close. The partially formed appendages may 

 be seen through the integument of the thoracic region a few hours before 



