INSECT PESTS 223 



Fourth Instar. Length, 11.4 mm. Appearance much as in third instar. Differs in 

 the fact that some of the dorsal stripes laterally now appear broken into short, ir- 

 regularly disposed lengths interrupted by dark ground color. There is a broader 

 lateral white band in or near which the spiracles lie. 



Fijth Instar. Length, 17.9 mrti. In general, this stage marks the change to greater 

 contrasts in the markings and to more brilliant colors. The appearance of red hues, 

 as on the ventral surface and in the paler portions of the body markings, is now 

 quite general. Head, orange brown with fine pale setae. Cervical shield and setigeral 

 warts as before, but the latter bearing pale setae. The shield may lose its dark color 

 in many specimens, however. All legs pale; claws of thoracic legs and crochets of 

 prolegs are brownish. Two continuous mid-dorsal white lines now enclose a darker 

 area appearing as a blackish band, in the middle of which lies a third white line. 

 Dorsum laterally to white spiracular band transversed by short white lines on a red 

 and gray ground which becomes darker near the lower edges and tends to concentrate 

 in segmental dark patches in some specimens. 



Sixth Instar. Length, 24.8 mm. Appearance much as in the fifth instar, but in 

 general more brightly colored and showing more pronounced individual variation in 

 the nature of the markings. Cervical shield not so dark, and less distinct from the 

 surroundings in many cases, although in some types of larvae it is very distinct. 



Pupa 



The pupa, just after it is rid of the larval skin, is very soft and delicate and 

 almost larviform. It is pale green on the head and thorax ; the wings are transparent 

 with the venation showing as whitish lines ; the abdomen is whitish and opaque, with 

 shades of rosy pink dorsally, and orange-colored spiracles. A large transverse rosy 

 spiracle anteriorly bordered with white lies on each side of the prothorax ; a trans- 

 verse median rosy spot between the eye ; and four black dots on each eye. 



In a half hour after the molt, the pupa has begun to contract and press its ap- 

 pendages into 'the places habitually taken by them and the pupa. The colors are 

 hidden by the darkening and hardening of the chitinous coat of the pupa. This change 

 to the natural shiny brown of the pupa takes place rather slowly over a period of 

 a day or more. The first portions of the body to darken are the head and dorsal 

 regions of the thorax and abdomen. 



Measurements of twenty-two pupae showed that there is comparatively little 

 variation in size in this stage. The length was found to average 19.1 mm., ranging 

 from 17.6 mm. to 20.6 mm. The breadth of the pupa at the widest point across the 

 back or dorsum is a little greater than the greatest depth from the dorsal to the 

 ventral surface. The average measurement in the first cases was S.S mm., while the 

 average depth was 5.4 mm. 



The original description of the adult (53) was translated by Ditman 

 and Cory (45) as follows: 



Adult 



A bombyx, with wings deflexed and yellowish; with a middle spot 'and posterior 



obsolete streak rather obscure. Habitat, islands of ScSiith America. Collector, Father 



Smith. Of medium size. The antenna simple. The' body yellowish with a more obscure 



middle spot. Posteriorly with an obsolete streak which is spotted with very small 



