Predaceous Insects and their Prey. 389 
dentipes attacking an Ephemerid, and Hmpis livida, the foe 
of Tortriz viridana and other small moths, also captured 
with a Phryganid. The 20 records of Hmpis tessellata 
—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 Bibionide (7) and to a far less extent the Zipulidex 
(4) are responsible for more than half. 
The 16 records of Hmpis livida include 6 moths 
(4 examples of Tortrix viridana, 2 of Crambidzx,) 1 Phry- 
ganid, and 9 Diptera, belonging to 5 different groups 
of which the Anthomyidx 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 Hmpinzw, though 
quite insufficient in numbers, render it likely that their 
diet also is normally confined to Diptera of various groups. 
Ocydromine.—The single example was found devouring 
a Mycetophilid. 
Tachydromine.—Only 5 captures are recorded for 3 
species. Of these 3 are Diptera (a Cecidomyid, a Myce- 
tophilid, and an Empid), the 4th a minute Braconid, 
the 5th a minute Cynipid. The evidence is entirely 
* It is pretty clear that the Rev. J. G. Wood was mistake in 
speaking of Hmpis 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 
empis, scientifically called Empis tessellata.” Now this latter is 
a large species, and Wood doubtless witnessed the attacks of the 
smaller H. livida. For the otherwise excellent popular account see 
“Common Objects of the Country,” London, N. D., pp. 101, 102. 
