THe CrANE-F LIES oF New YorK— Part I 881 
In some groups (Discobola, Liogma, Cylindrotoma, Tipula ultima, 
and others) the males mate with the females while the latter are still callow 
and teneral, in some cases even waiting beside the pupal case for the female 
to emerge, when she is at once engaged in copulation. In most cases, 
however, the female is fully developed and mature before mating takes 
place. When in copula most species rest quietly on some support, but 
nearly all species are quite capable of flying while still mated if disturbed; 
in such cases the larger sex takes the initiative —the female in the 
Tipulinae, the male in Eriocera longicornis and Teucholabis. Cases of 
mating between different species are rare, but in one instance the writer 
has noted the copulation of Phalacrocera tipulina with Liogma nodicornis. 
Oviposition 
The method of oviposition varies with the species and according to the 
structure of the ovipositor. In the forms with aquatic larvae (Eriocera, 
Hexatoma, and others) the eggs are laid directly in the water, the fly dip- 
ping during its fight. Many Tipula, such as 7’. zroquois, T. bella, and 
others, deposit their eggs regularly and methodically in algal beds at the 
edge of a stream. Tipula nobilis, one of the species having soft, blunt 
valves in the ovipositor, lays its eggs in soft mud or in moss. Many species 
of Limnophila deposit their eggs with great precision. The author has 
observed females of Limnophila alleni flying about low over the earth in 
cold, dark woods. They flutter along slowly and silently until a suitable 
place for egg-laying is found, consisting of a moss-covered, rotten log and 
the mud beneath it. The eggs are pushed firmly into their position by 
the acicular tergal valves of the ovipositor, considerable effort being made 
to place them securely. The rate of oviposition is not more than eight 
or ten eggs a minute, the female often pausing to rest for several seconds 
during the operation. When engaged in oviposition the fly is quite uncon- 
cerned with other agencies and may be picked up by hand. 
The species of Tipula with a serrated ovipositor, as described on 
page 875, undoubtedly have a specialized method of egg-laying, tho 
what this may be is not yet known. 
Photophilism 
Many species of crane-flies, in widely separated groups, are attracted 
to light, such species being termed photophilous, or light-loving. It is 
