222 DIVERSIOxNS OF A NATURALIST 



Tipula oleracea by entomologists, and is abundant in 

 Europe as well as in these islands. There are other 

 " species " of the. genus Tipula common in England, 

 namely, a smaller kind, with spotted wings, Tipula 

 maculosa, or the spotted crane-fly, and a large kind 

 called Tipula paludosa, which frequents marsh land. 

 There are many species of Tipula in other parts of 

 the world, and there are closely allied kinds which are 

 ranked in distinct genera, differing a little in certain 

 features from the genus Tipula. These all form, taken 

 together, the family Tipulidae. They, together with 

 the various kinds of gnats or " mosquitoes," the midges 

 and fungus-flies, form one of two divisions into which 

 the two-winged insects or Diptera are divided, namely, 

 those with long, thread-like feelers or antennae (Nemo- 

 cera — thread horned), the other division being those 

 with quite short antennae (Brachycera — short horned). 

 The latter group comprises the flies with thick, 

 heavy bodies, such as the common house-fly, the 

 bluebottle, the horse-flies, bott-flies, and tsetse-flies. 

 The long-horned group have usually long, narrow bodies 

 and long, narrow wings, which do not at once lie flat on 

 the back when the fly alights (as do those of the short- 

 horned group, as, for instance, those of the common 

 house-fly). The females of the common gnat (Culex 

 pipiens) and numerous allied species are bloodsuckers. 

 The various midges are mostly harmless, whilst others 

 have females which suck blood. The crane-flies do not 

 bite. The real feeding of all these gnat-like flies is done 

 when they are in the grub phase of their life, but the 

 females of some gnats and midges appear to have the 

 need of extra nourishment when in the fully-formed free- 

 flying state, in order to ripen their large bulk of eggs. 

 Hence, in some cases, they (but not the males) suck the 

 juices of plants and the blood of animals. 



