THE SUGAR-CANE MOTH BORER. 13 



more than 12 mm. long by 3 mm. wide. They are white at first, but 

 later an orange hue develops. They are lightly sculptured with an 

 irregular network of depressed lines which is visible with a micro- 

 scope. This sculpturing resembles the " pebble grain " of leather. 

 Just before hatching the black heads of the young larvse are plainly 

 visible through the eggshell, and the eggs assume a blackish hue. 



Eggs may be deposited on either side of a leaf. The fresh ones are 

 very difficult to find, their whiteness blending Avith the green of the 

 cane or corn leaf. They are securely glued to the leaf surface and in 

 nature are never detached before hatching. Having hatched, the 

 empty shells become translucent white. The appearance of a cluster 

 of eggshells from which the larva? have emerged has been well likened 

 to a fragment of cast snake skin. 



When parasitized the eggs gradually turn jet black and remain so 

 even with the emergence of the parasites. Because of their color, 

 parasitized eggs are much more easily detected in the field than are 

 the normal eggs. The holes made by the parasites in emerging are 

 readily discernible. (PI. II.) 



THE LARVA. 



The larva, which is the form of the insect most familiar to sugar 

 planters, is about 1 inch long by one-eighth inch wide. In this form 

 the insect commits its ravages. The head is brown and the body 

 white with brown spots. This is the summer coloration of the larva, 

 but in the winter it loses its spots and the body assumes a uniform 

 dirty white. 



Technical descriptions of both the winter and summer forms (full- 

 fed larvae ) have been published elsewhere by the senior writer (75), 

 and they have now been corrected by Mr. Carl Heinrich to conform to 

 the latest knowledge of lepiclopterous larval characters. His descrip- 

 tions are given below. 



General Characters. 



No secondary hairs. Legs and prolegs normal. Crochets triordinal and in a 

 complete circle. No anal fork. Prothoracic shield broad, divided. A narrow 

 pigmented shield on mesothorax, caudad of setae la and I&, bearing no setge. 

 Spiracles elongate oval; prothoracic spiracle twice the size of those on ab- 

 dominal segments 1 to 7; that on segment 8 slightly larger than prothoracic 

 and slightly dorsad of other abdominal spiracles. (PI. Ill, figs. 1, 3, 5.) 



Body setw (PL IV, fig. 1) moderately long; tubercles prominent, broadly 

 chitinized; IV and V on abdominal segments 1 to 8 under the spiracle and 

 approximate; prespiracular shield of prothorax narrow, horizontally elongate, 

 bearing only two setse (IV and V) situated ventro-cephalad of the spiracle, III 

 of prothorax absent; group VI bisetose on prothorax, mesothorax, and meta- 

 thorax ; 1 IV and V united on abdominal segment 9 and approximate to III ; 



1 This is the Pi group of Fracker which he erroneously describes as unisetose in the 

 Crambinae. See Fracker, S. B. The classification of lepiclopterous larvae. Illinois 

 Biological Monographs, v. 2, No. 1. 169 p., 10 pi. 1915. (See p. 87, 91.) 



