Tabanidae. 109 



in other species il is roundish, but always with the eggs in several 

 layers. The eggs may be abt. 2,5 mm. long and 0,5 mm. broad ; they 

 are cylindrical, a little curved, brown or black. The eggs are depo- 

 sited in summer, the iarvæ hibernate and the transformation to pupæ 

 and the development to imago taiie place in the foUowing spring or 

 summer. The Iarvæ live for a great part in water, but may also 

 live in the earth on moist localities and perhaps also on relativeiy 

 dry ones; when the time for the transformation to pupæ comes, the 

 Iarvæ living in water leave it, coming to the earth in the vicinity of 

 the water, and here they may rest for some time, before transforming 

 to pupæ. The Iarvæ are carnivorous and feed upon other aquatic 

 Iarvæ, they are also said to devour snails, earthworms and small 

 Crustaceans. 



The Tabani occur nearly everywhere, often in the vicinity of 

 water, in woods, and in adjacent pastures. The females attack cattle, 

 and they occur especially on hot days, then their bites may be a 

 great forment for the cattle; sometimes an exudation of blood from 

 the wound is seen. Packard refers cases from America in which 

 horses and cattle have been killed by their biting, these, howewer, 

 may be very rare cases. The males may also be seen to frequent 

 flowers, especially umbelliferes, f. inst. T. rusticus may be found so 

 in great numbers. Though the females may be very bloodthirsty, it 

 seems not probable that they live of blood alone. Hine (Department 

 of Agricult. Miscell. Papers, 1906, 25) states that the females of some 

 American species take other food than blood, and he says: „I dont 

 believe it vould be overstating the facts to say that specimens of this 

 sex may pass the period of adult life without taking blood at all." 

 He has often seen both sexes in foliage, and observed them sipping up 

 water that forms as a dew on the leaves; he refers that he has 

 observed a number of species of Chrysops and Tabanus of both sexes 

 feeding on the honeydew produced by Aphids. Already Westermann 

 (Germar. Magaz. Entomol. IV. 1821, 411—27) has an observation of 

 the exotic species Pangonia rostratu L. ; this species on account of 

 its long jjroboscis stings cattle, when on the wing, and stings so that 

 the blood runs from the wounds, but the species seems to like the 

 nectar of flowers more than blood as he frequently saw them on 

 flowers of Pelargonia; but unfortunately Westermann does not state. 

 wether it is also the females that frequents flowers. The males may 

 also be seen flying with great rapidity and hovering in the outskirt 

 of woods, often in the evening and morning, perhaps watching the 

 females; the copulation is said to take place in the air out of sight. 

 at all events it is very rare to see Tabani in copula. Yet Hine 1. c. has 



