Asilidae. 57 



downwards; the antennal sheaths lie over the lower part of the 

 eyes, directed to eacli side, they are compressed and have three 

 strong, downwards directed spines. At the base of the wing-sheath 

 there is a low tubercle, generally with a small spine, and at the base 

 of the leg-sheaths a pair of very small spines. On the dorsal side of 

 each abdominal segment there is a transverse girdle of strong spines, 

 short and somewhat longer alternating; each segment has a girdle of 

 strong hairs on the ventral side; along the sides there is on each 

 segment a somewhat tubercle-shaped elevation with an oblique row 

 of hairs going over in the dorsal spines; the last segment has at the 

 apex four spines, placed in a quadrate, each tapering to a bristly point, 

 between the lowermost pair there are two small, short spines. There 

 is a pair of thoracic and seven pairs of abdominal spiracles. The 

 sheaths of the legs reach to the hind margin of the second or third 

 abdominal segment in relation to the degree to which the pupa is 

 curved. 



The larvæ live in the earth, or sometimes below the carpet of 

 leaves covering the groimd in woods, and they may often be found 

 in mole-casts; they were formerly thought to live on vegetable or 

 decaying matter, but it is now clearly shown that they are carni- 

 vorous; they feed on other larvæ e. g. larvæ of difierent beetles; 

 sometimes they penetrate quite into the larva which they attack and 

 eat this quite empty before leaving it; they have been found in this 

 way in the larva of an Elaterid (Brauer 1. c. 28—29). Some species 

 {Erax, Asilus) also prey upon locust-eggs (Riley, First Rep. U. S. 

 Entom. Gomm. 303). The larvæ hibernate and the transformation to 

 pupa and developmont of the imago take place In the following summer. 

 The pupæ are found in the earth at the same piaces as the larvæ. 



The different species of Asilinæ occur in different piaces; some 

 species occur in woods, often especially in pine-woods, on open, sunny 

 piaces; these species are often seen sitting on the stems, watching for 

 prey and they take then a curious position; they sink somewhat on 

 the legs on one side while the legs on the other side are somewhat 

 stretched out and thus they get a characteristic oblique position. 

 Other species occur on sandy piaces in woods, on fields generally 

 also on dry and sandy localities, on heaths or along the shore and in 

 downs; these species are generally seen sitting on the sand. On the 

 whole dry and sandy districts are the common localities for the species. 

 The Asilinæ are strong robbers, they prey upon other insects of all 

 orders, and often the prey may be very large in relation to the Asilid, 

 even larger than this. Under each species I have given what I know 

 about its prey. 



