90 THE EARLY STAGES OF TABANIDvE 



a longitudinal fissure on the back of the head and thorax, reminding 

 one of the mode of escape of the harvest flies {Cicada), this pupa by- 

 means of the horns with which it is furnished had pushed itself up 

 to the surface of the earth. 



The pupa itself (Plate 12, Fig. 140) is, according to Riley, nearly 

 an inch and a quarter in length and a third of an inch in diameter. 

 It is cylindric, slightly curved, as in the figure, rounded at the head 

 and tapering at the extreme hind portion. The abdominal seg- 

 ments are, all but the first one, provided with a ring of fine yellow 

 bristles, pointed backwards. There is a stout thorn at the anal ex- 

 tremity, bearing six other thorns. 



The pupa state lasts but a few days and before the emergence of 

 the fly the pupa is pushed to the surface of the ground by means of the 

 bristles and thorns of the abdomen, with bending movements of the 

 body. 



It splits along the dorsal line and the fly emerges, leaving the pupa 

 case in perfect condition. 



Hart's description of the pupa (Plate 13, Fig. 163) contains some 

 additional details. 



"Pupa, Male. — Length 30-v35 mm., diameter 7.5 mm. Yellowish fuscous 

 with a brownish tint, thorax not paler. Palpal sheaths distinct, short, very 

 narrowly separated by a depressed space. Abdomen roughly wrinkled and sub- 

 opaque. Spiny fringes tipped and annulated with black. Otherwise as in the 

 pupa (female) of T. stygius'^ (described by Hart in the same paper). 



Hine (1906) gives another description of the pupa: 



"Pupa [Plate 11, Fig. 124; Plate 13, Fig. 164] about U inches in length. 

 Color brownish yellow. Antennal and other tubercles of the head darker than 

 the surrounding parts. Prothoracic spiracle slightly elevated, clear brown in 

 color, reniform and oblique, rima gradually curved to near the dorsal end, where 

 a distinct hook is formed by a sharp bend. Abdominal spiracles nearly round; 

 rima of the first short and gradually curved and with a slight hook at the dorsal 

 end. Terminal teeth [Plate 13, Fig. 164] arranged in pairs, a ventral pair and a 

 pair on each side formed by a dorsal and a lateral tooth. The distances between 

 these teeth are variable; the two dorsal are nearest together, then follows the 

 distance between a dorsal and a lateral, the distance between the two ventral, 

 while the distance between a ventral and a lateral on each side is greatest of 

 any." 



