WERNER MARCHAND 75 



parently showed a preference for this environment and had been 

 seen to work their way into a decaying leaf. They did well under 

 these conditions; only a few of them died, and on July 22, in the 

 afternoon, the first soft pupa was found, the larval skin still adher- 

 ing to it, and identical with those found dead in the water. 



A few days later, when a search was again made for the larvae, 

 none of them were found, but instead it was discovered that they 

 pupated in the interspaces of the somewhat defective brick walls of 

 the reservoir, and here some pupae as well as larvae were collected, 

 of which the latter were more or less contracted in preparation for 

 their metamorphosis. From these pupae the first fly was obtained 

 on July 27, in the morning. 



The duration of the larval stage is about three weeks; the duration 

 of the pupal stage Marno could not ascertain, leaving his material 

 to Brauer to study. 



The larva (Plate 6, Figs. 89, a, b, and 90, a, b, c) has been de- 

 scribed by Brauer (1883), who reports it to be aquatic, being found in 

 pools and puddles. A translation of Brauer' s description is given 

 below. 



Larva, when extended, slender and spindle-shaped; when contracted, obtusely 

 cylindric, the anterior and posterior segments being retracted in the latter case. 

 The body consists of a head capsule and eleven segments. The cuticle has a 

 striped appearance because of the many closely arranged longitudinal furrows. 

 The first three segments and the under surface are bone-white (yellowish white), 

 the dorsal surface of the remaining segments shows beautiful grayish brown pat- 

 terns on a white background, brought about by microscopic pubescence. The 

 head capsule (Plate 6, Fig. 90, a, b, c) is narrow, formed like that of all tabanid 

 larvae, compressed, and can be retracted into the second segment. It consists 

 of four plates which posteriorly are not connected, and of which the two middle 

 ones are drawn out into long rods. The lateral plates show on half their length 

 on the outside an irregularly rounded and convex eye-spot on each side. At the 

 anterior end is a comb-like upper lip reaching above and between the mandibles. 

 On each side of its base there is a cushion-like projection thickly beset with mostly 

 two-pointed bristles, on which the antennae are inserted, which are short and two- 

 jointed. The first joint is cylindric, the second divided lengthwise into two 

 parts. The exterior point is shorter than the interior. Below and to the inside 

 of the antennae are the hooked and more strongly chitinized mandibles, which 

 may be moved up and down parallel to one another. Their surface is trans- 

 versely sulcate; consequently the anterior convex margin is serrately incised. 



