Predaceous Insects and their Prey. S89 



dentipcs attacking an Ephemerid, and Empis livida, the foe 

 of Tortrix viridana and other small moths, also captured 

 with a Phryganid. The 20 records of Eiivpis tcssellata 

 — all Diptera — render it improbable that other insects 

 are attacked.* The variety of prey within the limits of 

 this Order is remarkable, no less than 8 families or sub- 

 families being divided between the 20 victims. Of these 

 the Bihionidm (7) and to a far less extent the Tipulidc'B 

 (4) are responsible for more than half. 



The 16 records of Pmjns livida include 6 moths 

 (4 examples of Tortrix viridana, 2 of CrambidiB,') 1 Pliry- 

 ganid, and 9 Diptera, belonging to 5 different groups 

 of which the Anthomyidm furnish the largest number of 

 victims (3). Of special interest in this species is the series 

 of 9 examples (264-272) with prey captured by Mr. 

 H. St, J, K, Donisthorpe at Huntingfield, Kent, on the 

 evening of July 21, 1906. In circumstances such as these, 

 when an abundant predaceous species is feeding in a 

 locality where insects are common and varied, we obtain 

 the most valuable information possible as to the range of 

 its preferences. It is to be hoped that much time and 

 labour will be directed to the collection of all possible 

 material whenever such exceptionally favourable oppor- 

 tunities arise. The deeply interesting results of Mr. 

 Donisthorpe's captures of ^. livida, and of the two series of 

 Dasypogon diadema (15-41 and 43-54) observed at nearly 

 the same times at La Granja, indicate the importance and 

 interest of the conclusions which may be thus reached. 



The records of the other species of EmpinsR, though 

 quite insufficient in numbers, render it likely that their 

 diet also is normally confined to Diptera of various groups. 



Ocydrominm. — The single 'example was found devouring 

 a Mycetophilid, 



Tachydrominx. — Only 5 captures are recorded for 3 

 species. Of these 3 are Diptera (a Cecidomyid, a Myce- 

 tophilid, and au Empid), the 4th a minute Braconid, 

 the 5th a minute Cynipid. The evidence is entirely 



* It is pretty clear that the Eev. J. G. Wood was mistaken in 

 speaking of Emp'is tessellata as the captor of Tortrix viridana. Thus 

 he says : — " There are several species of this useful fly, one attaining 

 some size ; but the one that claims our notice . , . is the little 

 enipis, scientifically called Enipis tessellata." Now this latter is 

 a large species, and Wood doubtless witnessed the attacks of the 

 smaller E. livida. For the otherwise excellent popular account see 

 "Common Objects of the Country," London, N. D., pp, 101, 102, 



