WERNER MARCHAND 129 



The eyes change color after two or three days. Eye coloration and 

 stripes of abdomen visible two to three days before hatching. Pupal 

 shell very transparent. 



Tahanus orientis Walker. — A Tahanus occurring in North India, 

 Nepal, Bhutan, particularly in high elevations; according to Baldrey, 

 "by far the largest of the species caught at Muktesar (7,500 feet); 

 it is caught at the beginning of March and appears then to be quite 

 full grown (owing to its torn and worn out condition)." 



According to Baldrey, who tried to breed the species for experi- 

 mental purposes, it begins laying its eggs during the last weeks in 

 April, and all flies dissected up to June 19 were found full of eggs. 



The eggs when first laid are of a creamish white color, but after a 

 few hours this changes to a cigarette-ash color. They are laid in 

 batches resembling bunches of bananas. 



Four lots of eggs were found in jars containing iiies; in two cases 

 the only fly in the jars was found dead. 



Tahanus par Walker. — Of this African species we possess full de- 

 scriptions of the Qgg, larval, and pupal stages by King (1910), who 

 not only secured oviposition in captivity, but also bred the species 

 through from the egg to the adult stage. 



Occasional specimens of this tabanid were met with on the White 

 Nile from Gebelein southwards. In the country behind Bor females 

 were abundant and seemed to spend their time resting on foliage, 

 waiting for approaching animals which they would attack at once. 

 No eggs could be found, though a careful search was made in all 

 the places that were considered likely to serve as breeding grounds; 

 hence a number of females, gorged with blood, were placed in a 

 breeding cage, in which was also a dish containing mud, water, and 

 growing grass and weeds. The flies fed on sugar and water, and 

 though the majority died within the first two days, the survivors 

 eventually produced three small batches of eggs (Plate 1, Fig. 10). 

 The eggs obtained in this manner were deposited on May 23 and 24, 

 on the under sides of the leaves of a water weed. Unlike the eggs of 

 most members of the genus Tabanus, they were not closely packed 

 in a rounded mass, but placed vertically and separately though in a 



