WERNER MARCHAND 89 



posterior border of the segment, and a dorsal (?) groove continued for the entire 

 length. These grooves and a number of irregular dots on the posterior part are 

 dark colored, while the remainder of the segment is light. Mesothoracic segment, 

 on each side, with four longitudinal grooves, which reach nearly the entire length. 

 The dark markings on this segment include a narrow anterior border, the lateral 

 grooves, and a number of irregular dots near the posterior margin. The meta- 

 thoracic segment is like the last except that the dark color on the anterior mar- 

 gin is wider and the posterior, instead of being dotted, is uniformly brown. The 

 abdominal segments are each similar to the metathoracic, but the dark mark- 

 ings in the region of the lateral grooves are more or less abbreviated. Last ab- 

 dominal segment with two pairs of dark markings; the ventral pair extend the 

 whole length of the segment and are connected just behind the anal prominence 

 by a cross-band; the dorsal pair are oblong, somewhat irregular in outline, and 

 extend from the anterior margin to beyond the middle of the length. At the an- 

 terior ventral border of each of the first seven abdominal segments is a trans- 

 verse series of prolegs, three on either side of the midventral line. These pro- 

 legs are located within the dark transverse bands, but are lighter in color than 

 these and prominent enough to be seen easily. Above the prolegs on either side 

 of the middorsal line is a small swelling which appears as a rudimentary proleg; 

 before the two is a distinct transverse light spot still within the dark area." 



"The head of the larva is very small for so large an insect and the mouth 

 parts are minute. The mandibles consist of two strongly chitinized pieces, and 

 work by being pushed endwise backward and forward. When drawn in, the 

 anterior ends point directly forward, but when protruded, these same ends point 

 downward and backward, thus forming a pair of hooks by means of which the 

 prey is held. The larva is able to protrude its mandibles very quickly and to use 

 them very effectively on soft-bodied invertebrates on which it is known to feed." 



W. A. Riley and Johannsen (1915) have also figured the full grown 

 larva of Tahanus atratus (Plate 3, Fig. 45), and Malloch (1917) fig- 

 ures the head and first segment of the larva (Plate 5, Fig. 77). 



On the pupal stage we have information, in addition to Walsh's 

 description, by C. V. Riley, Hart, and Hine. 



Riley reports that his larva transformed to pupa within the ground 

 during the early part of July ; it remained in this state but a few days 

 and the fly issued July 13, and soon made its presence known by its 

 loud buzzing inside the jar. It was a perfect specimen, and the 

 pupal integument was sufficiently firm and polished so that by care- 

 fully washing off the earth an excellent cabinet specimen was ob- 

 tained, which retained almost the exact form and appearance of a 

 living pupa. Before the escape of the fly, which was effected through 



