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HAROLD H. KING— SOME OBSERVATIONS ON THE BIONOMICS 



to be chosen for the act ; one was taken ovipositing at 11.40 a.m. and 

 another at 4.40 p.m., and unlike T. biguttatus, Wied., the only other seroot 

 which the writer has observed ovipositing in the field, the female of this 

 Tabanid does not lose her natural wariness while engaged in depositing her 

 eggs. In foct, she is often more difficult to capture than when merely 

 sunning herself on a rock. 



Fig-. 5, — A rock at Khnr Arbat, showing sites selected by Tabamis Ja'tu/i for 

 ovipositing (indicated by crosses) ; the three lower crosses represent 

 freshly laid egg-masses. 



The egg-masses (fig. G, «) vnry in size, and no count of the number of eggs 

 contained was made, but the average mass is believed to consist of about 

 five hundred. When freshly laid the mass is glistening white and can be 

 seen from a considerable distance; but within a few hours it takes on a 

 mottled grey hue, w^hich so closely resembles the colour of the rock that it 

 is not easily detected. While the fly is occupied in laying her eggs, numbers 

 of a tiny Hymenopteron assemble and proceed to add their eggs to the mass, 

 continuing to do so after the fly has gone away. From some twenty 

 egg-masses collected from the rocks about equal numbers of this egg- 

 parasite and of the Tabanid larva were obtained. Specimens have been sent 

 to the Scientific Secretary of the Entomological Research Committee for 

 determination. 



