06 GLOSSINA BEEVIPALPIS : LAEVA AND PUPA. 



" If," writes Stuhlmann, " the new-born larva be placed in a 

 glass dish or on blotting-paper, it crawls about for a time 

 exactly like an ordinary fly-maggot, after which it becomes 

 stationary and soon contracts, its chitinous integument thickens 

 and darkens, and in about three-quarters of an hour it has 

 assumed the appearance of a ' coarctate ' pupa. If, however, 

 the larva be transferred to moderately damp sand, it at once 

 burrows into it, making a straight tunnel ; thus in one case a 

 larva penetrated to a depth of 8 "5 cm. (3.\ inches). Under such 

 conditions, from an hour and a quarter to an hour and a half 

 elapsed before the change to the pupal stage was completed. In 

 dry sand a larva did not burrow so deeply, since, as it burrowed, 

 the sand continually fell in, but nevertheless it reached a depth 

 of from 2 to 3 cm. (| to 1^ inch). We may assume that in 

 nature the larvae behave in a similar way ; the fly will deposit 

 its ofispring on a spot which is sheltered and slightly damp, and 

 the larva will at once burrow beneath the surface." 



The jJMjja (Figs. 5 a, 6 a, pp. 5, 7), which is of the usual black 

 or clove-brown colour, measures about 7*5 to 8 mm. in length, 

 by 4 to 4*5 mm. in greatest breadth ; " the shape and dimensions 

 of the tumid lips and the shape of the notch between them are of 

 course the same as in the larva. At Amani, the duration of 

 the pupal stage was found by Stuhlmann to be from thirty to 

 sixty-five days, according to the temperature ; when pupae were 

 kept in the breeding-cage at 30° C. (86° F.) the flies emerged on 

 the average in about thirty-six days. The pupal stage appeared 

 to Stuhlmann to last somewhat longer in this species than in 

 G. tachinoides. 



Although a Glossina escapes from its pupa-case in precisely 

 the same manner as any other Muscid fly, it may be of interest 

 to quote Stuhlmann's account of the emergence of the imago of 

 G. brevipalpis. "The fly," writes Stuhlmann, "bursts ofi^ the 

 cap of the pupa- case, and protruding from the opening its 

 cephalic vesicle,"]" forces its body-fluid into the latter, so that its 

 body becomes sufiiciently thin to be able to creep out of the 

 puparium. Immediately after the insect has made its escape the 

 cephalic vesicle is retracted into the interior of the head and 

 never used again. In a short time the young fly draws air into 



* So far as may be judged from an examination of seven specimens 

 from Amani {Dr. Vosseler) ; since these are from larvae deposited in 

 captivity, it is possible that in certain cases the dimensions are slightly 

 subnormal. 



t Termed by Dipterists the ptilinum. — E. E. A. 



