786 



MK. J. a. U. FRKW ON THE liARVAL '. 



'n\ Chlorops is probably due to the xinnsually large size oftlie 

 maxillary palps and their close approximation to the anterior 

 edge of the moi.th-opening. Each pre-oral sense organ is a 

 slightly raised papilla bearing several small rounded bodies similar 

 to those on the maxillary palps. 'According to Keilin (9) tlie pre- 

 oral sense organ is innervated by a bi'anch of the nerve which 

 supplies the maxillary palps, of which, according to him, it is 

 probably a ])art. 



The po.-vition of the antennce (a.) is peculiar in being nob 

 anterior, but lateral, on a level with the anterior border of the 

 month and actually, tlierefore, posterior to the iriaxillary palps. 

 Each is two-jointed, tlie basal joint being little more than a, small 

 l)a[)i]la with a llattencd apex. The second joint, which lits into 

 the apex of the lirst, is a cylindrical body of firm yellow^ chitin 



Text-figure 2. 

 C 



0-2 mm. 



C. tceuiopiis. Voiitn.l viuw of larval head. 



A. Thoracic sense-organ and neiglibonring chitiiious ilenticles. 

 ]}. Abdominal cliitinous denticles. 



with a rounded apex. Internally, at about one-third of its height, 

 the second joint is produced into a circular ledge whose inner 

 edge is bent at right angles towards the base of the antenna. 

 "Keilin (9) describes, in connection with the antenna of Polhnia 

 r«(Zis Fabr., a "petit batonnet cliitineux," one end of which is 

 attached to the outside of the base of the si-cond joint of the 

 antenna while its other end is in connection with a " bulbe 

 nerveux." In a later paper (10) he describes a similar organ in 

 the larval antenna of Graphomyia maculcUa Scop, with the 

 difterence, however, that it arises from the inside of the second 

 antennal joint, and he seems to imply that such an appenda<»e to 

 the antenna is universal in Oyclorrliaphous larvie. I have tailed 

 to find this appendage in the larva of Chlorops or any other 

 Acalyptrate larva, and although the number of species examined 



