WERNER MARCIL\ND 133 



scatter its brood as many other species of flies do, but deposits the 

 eggs in a single mass. 



The eggs were counted, and their number found to be about 350 

 to 400. Also the hatching of young larvae was observed, and the 

 duration of the egg stage found to be from ten to twelve days (Kollar) . 



From the egg masses collected by Mann, besides young Tahanus 

 larvae, also ichneumonid flies (parasitic Hymenoptera) were observed 

 to hatch; to Kollar and Mann consequently credit is to be given for 

 the first discovery of hymenopterous egg parasites in tabanids, 

 though no description is given (see under Parasites of the early 

 stages of Tabanidae, page 182). 



The publication of Kollar has been quoted in detail by Lecaillon, to 

 whom we owe further studies on the early stages of Tabanus quat- 

 uornotatus, chiefly on the oviposition of this species. Lecaillon 

 found the species, with a related form, Tahanus hromms, abundantly 

 at Gouy, Aisne, France, in May, 1904. Oviposition of Tahanus 

 quatuornotatus was observed on May 24, 1904. In the afternoon of 

 a sunny day, on a wooded and not especially damp hillside, a female 

 was found sitting immobile on a dry branch of a weed {Origanum), 

 the head turned downwards, at a distance of 35 to 40 cm. from the 

 ground. The eggs already laid formed a conspicuous white mass. 

 On coming nearer, Lecaillon ascertained that the Tahanus, which 

 under every other circumstance is likely to take flight, was not dis- 

 turbed and continued to oviposit. Lecaillon broke off the branch 

 with the insect on it, placing the whole in a Jar. The female con- 

 tinued to oviposit for about ten minutes, when it ceased and left 

 the branch. The egg has been figured by Lecaillon. 



Lecaillon calls attention to the fact that, as already stated by 

 Kollar, the ovipositing female is somehow indifferent to what is 

 going on around her, a fact which should be taken into account in 

 understanding the habits of adult tabanid flies. 



Concerning the early stages, we learn from Lecaillon's observations 

 on this species that oviposition in some tabanids may take place in 

 comparatively dry and not necessarily in a damp environment. In 

 both Mann's and Hart's observations it took place in a moist environ- 

 ment. As among insects frequently not only the necessities of em- 

 bryonal but also of larval life may be anticipated from the manner 



