26 



BULLETIN 1218, U. S. DEPARTMENT OF AGRICULTURE. 



found mostly in swampy areas overgrown with grass, on or near the 

 surface of the soil in masses of decaying vegetable matter. They 

 were collected in the higher mountain valleys as well as in the floor 

 of the lower valley. They were seldom found in the loose gravel by 

 streams or in the loose humus where T. punctifer was so abundant 

 around the shore of the lake. 



Pupa. 



(Fig. 14, E; PI. II, C) 



Length about 15 millimeters. Width of thorax 3 millimeters. Pale yellowish. 

 Wedge-shaped teeth at anterior end not prominent. Palpal sheaths not prom- 

 inent. Dorsum of prothorax smooth except for two slight rugosities, one at 

 either side of the median line, slightly posterior to bases of palpal sheaths. 

 Rima of thoracic spiracle broadly curved, not forming distinct hook. 



Circlet of bristles on abdominal segments not double as in Tabanus punctifer. 

 Dorso-lateral fringes on eighth segment normal. Ventral fringe on this seg- 

 ment continuous across median line. Of the terminal teeth on anal segment, 

 the two lateral teeth are larger than the others, and these are arranged almost 

 in a straight line with the two dorsal teeth. 



Described from a single male specimen with the aid of a binocular 

 microscope. 



Table 5 contains the records of those individuals which were suc- 

 cessfully reared from larva to adult in the. laboratory. 



Tabu: 5. — Pupal period of Tabanus plmenops. 



No. 



Date of Date of 



pupation. emergence. 



6873-1.. 

 6875-1.. 

 6884-8.". 

 6884-9.. 

 6884-12. 

 6884-24. 

 7505-1.. 

 8700-102 



June 2,1917 

 June 19,1917 

 July 15,1918 

 July 2,1917 

 Aug. 2,1917 

 July 15,1918 

 July 15,1918 

 July 16,1919 



June 25,1917 



July 

 July 



6,1917 

 30,1918 



July 16,1917 



Aug. 

 Julv 

 July 



19,1917 

 29, 1918 

 29,1918 



July 28,1919 



Duration 

 of pupal 

 period. 



Days. 

 23 

 17 

 15 

 14 

 17 

 14 

 14 

 12 



Sex. 



Male. 



Female. 



Female. 



Male. 



Female. 



Female. 



Female. 



Male. 



The average pupal period was 15.7 days. The complete life cycle 

 was not determined. It is certain, however, that not more than one 

 generation a year is produced. 



TABANUS INSUETUS Osten Sacken. 



Description of Adult 



Tabanus insuetus is a small gray species with colored bands ex- 

 tending transversely across the eyes. (PI. Ill, A,B.) Osten Sacken's 

 description (11, p. 219) is as follows: 



Tabanus insuetus n. sp. — Belongs apparently to the subgenus Atylotus. 

 Eyes pubescent, although in the female specimens the pubescence is often 

 hardly perceptible ; in life, pale olive-green, with a single very narrow brown 

 stripe in the middle (distinct even in dry specimens) ; no vestige of an ocellar 

 tubercle; frontal callosity rather small, variable in size, narrower than the 

 front; third antennal joint rather broad and short, with a short and stout 

 annulate portion; palpi stout at base; first posterior cell broadly open; base 

 of upper branch of third vein knee-shaped, in many specimens with a stump 

 of a vein. All these characters would justify the location of the species in 



