WERNER MARCHAND 69 



the first one thick and long, the second short and narrow. There are no bristles 

 at the base of the antennae. The eye-spots are small, perhaps more distinct in 

 life, and situated behind the middle of the head. The whole head is deeply 

 retractile. The body is pure white in color with many longitudinal striae, and 

 bearing, on the fourth to tenth segments, small fleshy warts on the lateral and 

 ventral sides, each segment having four. These warts can be retracted, giving 

 the larva an almost smooth appearance. The last segment ventrally with a 

 thick half globular anal prominence, and posteriorly with a short conical structure 

 with a vertical two-lipped fissure. The lips of the latter are strongly chitinized, 

 transversely sulcated, each of them leading to one of the main tracheal trunks; 

 they represent the posterior spiracles of the larva, while the small anterior 

 spiracles are situated on the posterior half of the second segment. 



The whole structure of these respiratory organs indicates that the 

 larva had not lived in water or left it only for pupation, as, according 

 to Brauer, in all tabanid larvae of terrestrial habitat the posterior 

 spiracles are analogous in structure, while the aquatic larvae of Ta- 

 hanus autumnalis and Hexatoma pellucens are enabled to extend the 

 last segment like a telescope, showing a similar fissure only at the end 

 of this tube. 



A much more detailed description of this larva is given byPerris 

 (1870), who found it twice, and each time in a single individual, 

 in the decayed wood of old pine stumps. Of the two specimens 

 found one was sacrificed to be studied; the second one metamorphosed 

 and produced, to the surprise of the observer, the species Hcematopota 

 pluvialis. This fly, as he says, is very common in regions of France 

 where there are no pines, and so abundant in the Landes that he 

 could not have missed the larvae if the stumps or the bark of dead 

 trees were its normal place of development, as he had especially 

 studied all insects inhabiting the pine. Consequently, Perris as- 

 sumes that the insect has deviated from its ordinary habits. How- 

 ever, the larvfe were found in the pine wood detritus itself where they 

 apparently had lived, and in which the larva mentioned changed to 

 pupa after three months. 



A translation of Perris' description of the larva (Plate 6, Fig. 82, a-e) 

 is given below : 



Larva (figured) 12 mm. in length. Smooth, hard, leathery (coriaceous), cylin- 

 dric, attenuated at both ends, anteriorly more than posteriorly, very finely and 

 densely striated in a longitudinal direction. 



