170 AN ACCOUNT OF BRITISH FLIES. 
entomologists, both in its pre-larval life as well as during its trans- 
formations, and we shall consider this subject more fully when dealing 
with their larval life. 
The characters of the family are briefly as follows : Head small and 
often retracted under the thorax, which is without any transverse 
suture. Ocelli absent or rudimentary. Wings long, narrow, costal 
vein ending near the tip of the wing, no veins along posterior margin. 
Antenne with from six to fifteen joints, which are densely pectinated 
in the males, but often simple in the females and smaller. Legs long 
and slender, tibize and tarsi nearly cylindrical. 
The following are the synonymous names of the family : 
(Tipularie culictformes, Mg., Macq. 
Culicites, Newman. 
Chironomide =4 Tipulidae, Leach. 
Chironomit, Zett. 
| Chironomine, Roud. 
The geological distribution is, strange to say, wide, we naturally 
should not expect to find any traces of such delicate insects as the 
“midges” we are considering in the rocks of any remote period, 
such, however, is not the case, for even in Mesozoic rocks we find 
representatives of these delicate flies. The Lias of Dobbertin fur- 
nishes us with a species referred to the genus J/acrofeza, and another 
species of the same genus has been figured by Brodie from the 
English Purbecks. The latter author also figures from the same 
horizon two possible Chironomi. There are also two other species 
possibly belonging to this family, namely, Cecidomium grandevum, 
Westwood, and Corethrium jpertinax, Westwood, from beds of 
Purbeckian age. But as in many other fossil insects, of which we 
have only fragmentary remains, there is some doubt as to their true 
relationship, they might possibly be intermediate types between the 
Chironomide and Culicide. ‘The species figured by Brodie under 
the name of Rhyphus priscus is most probably a member of this 
family and not of the family to which Brodie referred it. 
When we reach the Tertiary beds we find a very different aspect ; 
as we should expect, the amber, which is such a wonderful preserver 
of insect life, contains many of these delicate flies, some in a beautiful 
state of preservation. Loew has described several species of Zanypus 
and many of Chivonomus and Ceratopogon. Burmeister and Giebel 
also record the presence of the two latter genera in amber. Not only 
do we find the perfect insects but also the pupz in a state of perfect 
preservation, and occasionally a maggot has been found. Besides 
