122 THE EARLY STAGES OF TABANID^ 



as 7 mm., while others measured only 3 mm. At this date angle- 

 worms were given for food, and were accepted readily, and appeared 

 to be as satisfactory as the crustaceans, but it would seem that the 

 latter are preferable for the stage just after hatching. 



On July 27 some of the larvas were 10 mm. in length, and on August 

 2 the same specimens measured 12 mm.; thus at this stage they grew 

 more rapidly than when they were younger. They fed actively till 

 about the middle of September, when they had become apparently 

 full grown, or 25 mm. long. Length in the larvae of tabanids is, ac- 

 cording to Hine, not a satisfactory means of indicating the size, for 

 the segments telescope on one another in such a way that it is difficult 

 to take two measurements exactly alike, but an endeavor was made 

 in this case to make the different measurements similar, so I believe 

 that those given are considered sufficient to indicate the comparative 

 sizes of the different ages. After September 15 the few specimens 

 remaining alive buried themselves in the sand of the breeding jars 

 and were quiet most of the time until March 10, when one pupated, 

 the adult emerging on the 25th of the same month. The others died 

 before the pupal stage was reached. Hine has noted that larvs of 

 various species of tabanids taken from their natural habitats during 

 the winter did not produce adults in the spring much before the 

 same species appeared naturally, but in this case, where the specimens 

 was kept under artificial conditions during its entire life, the adults 

 appeared almost two months earlier than is normal in nature. 



Hine's description of the larva follows: 



"rAe mature larva [Plate 3, Fig. 44] is not notably different from those of 

 other species of Tabanus so far as form and appearance are concerned. The color 

 is a dirty white with a pinkish shade over most of the body; the prolegs are not so 

 prominent as in many species, and on this account specimens appear somewhat 

 maggot-like. On either side of the body is a longitudinal row of very small black 

 spots or specks, one to each segment and located just above the ventral pro- 

 legs; these spots are lacking on some of the anterior and some of the posterior 

 segments; their presence appears to be characteristic of the species, at least so far 

 as my acquaintance with different larvae goes. Mature specimens are about 25 

 mm. in length." 



Hine has not taken the larva of this species in its natural habitat, 

 therefore he cannot say where it is to be found, but he thinks that 



