WERNER MARCHAND 145 



Tabanus speciosus Ricardo. — In Madras, India, but rather rare; 

 feeding on cattle with Tabanus striatus and albimedius, and similar in 

 size and appearance to the latter. 



According to Patton and Cragg, this species lays its eggs always 

 on the leaves of water-lilies growing in deep water. The number of 

 eggs laid is between 500 and 600. The process of oviposition is said 

 to be similar to that of Tabanus albimedius, but Tabanus speciosus, in- 

 stead of forming a V-shaped mass as is usually the case with the 

 larger tabanids, lays its eggs in a round heap, which it then plasters 

 over with a chalk-like substance, almost completely covering the 

 eggs. The egg mass is figured (Plate 1, Fig. 19), 



The larvce of the larger Indian tabanids, including this species, are 

 powerful swimmers and have air sacs connected with their tracheal 

 tubes, so that they can float or sink at will. A description of the 

 larva is not given. 



Tabanus spodopterus Meigen. — A common European species. Ac- 

 cording to Schiner, very common in Austria, at the Neusiedler See. 

 Brauer (1883) gives an illustration of the larva (Plate 6, Fig. 87, a-f), 

 which he found, in the month of May, under dry leaves on the 

 ground. 



Tabanus striatus Fabricius. — The early stages of this species have 

 become known through Mitzmain's work, which is the most thorough 

 investigation into the life history of a tabanid species which we pos- 

 sess. We cannot enter here upon his results in as far as the habits 

 of the adult fly and its part in the transmission of disease is con- 

 cerned, but have to limit ourselves to report on the results obtained 

 on the early stages of this species. 



The eggs of Tabanus striatus (Plate 2, Figs. 22 to 27) were not found 

 in the field, but Mitzmain was able to obtain them from females 

 ovipositing in captivity. A large case was built for this purpose 

 provided with a tank of water, growing plants, and two animals 

 (carabaos) as a source of food for the flies. In a short time females 

 were observed feeding on the hosts and several were found ovipositing 

 in various places about the enclosure. 



The time selected for egg laying under the conditions provided was 

 invariably during the early afternoon, never later than 2 o'clock. 

 This was observed in nearly fifty instances. 



