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BULLETIiSr 1357, U. S. DEPARTMENT OF AGEICULTUEE 



PUPA STAGE 8 



The pupse (fig. 9) at first are whitish throughout. The eyes are dark 

 and the mandibles become brown about the middle of the pupation period. 

 When the pupa is about, three-fourths mature the tips of the metathoracic 

 wings become dark gray, following which the mesothoracic wings, which de- 

 velop into the elytra of the adult, become somewhat brownish owing to the de- 

 velopment of the chitin. When first formed, with the wings still folded close to 

 the body, the pupa is from 3.8 to 4.3 millimeters long and 1.9 to 2.1 millimeters 

 wide. As it develops the pupa becomes somewhat shorter and a little stouter, 

 approaching the shape of the adult. The head of the pupa is bent down slightly 

 and the legs folded against the under side of the body, the metathoracic pair 

 being applied against the sides of the abdomen, while the femora of the pro- 

 thoracic and mesothoracic pairs project at right angles, with the tibiae folded 

 up close to the femora. The wing pads are wrapped around the metathoracic 

 legs. The antennae are held close to the body and curve under the distal part 

 of the femora of the two anterior pairs of legs. The front of the head bears a 

 few long setse with bulblike bases ; three transverse rows of similar hairs are 



present on the dorsal side of the pro- 

 thorax, and the scutellum bears one on 

 each anterior corner with a pair on 

 either side and slightly in front. There 

 are sis on the upper side of the meta- 

 thorax and a row of eight on each ab- 

 dominal segment. The last segment of 

 the abdomen terminates in two simple 

 spines which curve dor sally. The spines 

 are dark in color and become quite 

 dark when the pupa is almost mature. 

 In front of these h'ooklike projections 

 are two pairs of lateral setae, one on the 

 last and the other on the next to the 

 last segment, which project backward. 

 A strong, curved hook, similar to the 

 anal hooks, arises from the posterior in- 

 ferior angle of the tibiofemoral articu- 

 lation of the metathoracic legs. These 

 curve down and in toward the body 

 and each bears a long bristle near the 

 point. The anterior angles of this joint 

 bear two long setae with inflated bases, 

 and similar setae arise from the ante- 

 rior angles and the middle of the in- 

 ferior margin of the corresponding joints of the other two pairs of legs, which 

 do not bear spines, however. The ventral surface of the pupa bears no setae or 

 spines. The abdomen is slightly curved ventrally. 



9. — Strawberry 

 view of pupa- 



Dorsal 



PUPATION, LOCATION OF PTJPA, AND LENGTH OF PUPAL PEEIOD 



The full-grown larvae hollow out small earthern cells and there 

 change to pupse. (Fig. 4.) Most of the pupse collected have been 

 found within 2 inches of the soil surface, and when the cells were 

 broken into the disturbed pupse would move their abdomens back 

 and forth very vigorously with a motion which apparently served 

 the purpose of keeping the cavity hollowed out. When sifted soil 

 is dropped on a pupa resting in one-half of its cell, the particles are 

 swept out of this cavity by three or four movements. 



The duration of the pupal stage was from 5 to 17 days, as indi- 

 cated in Table 11, but from 8 to 11 days appeared to be the usual 

 time required for this stage. 



8 The description of tlie pupa is based on. that given by Forbes (13, pp. 152-153) , vnth 

 some additions and modifications. 



