MYCETOPHILID.I]. 47 



varying distances from the base according to the species, and 

 perhaps too much importance has been placed on this as a 

 character in classification. The 5th vein is widely forked at the 

 base, the upper branch sometimes detached ; 6th incomplete ; 

 7th rudimentary or absent. 



Life-history. — The metamorphoses of a good many species, 

 mostly European, are known, but no Oriental species has yet 

 been studied in the earlier stages. 



The eggs are laid singly on the underside of a leaf, or on 

 the pileus of a fungus, but in the case of Sciara tliey may 

 frequently be joined together end to end in a loug string, and 

 I have often met with specimens of this genus with such a string 

 of eggs still attached to the abdomen, from which by slight 

 pressure further eggs could be made to extrude. 



The larva itself has generally the appearance of a very elongate, 

 sub-cylindrical, semi-transparent, worm-like maggot, of twelve 

 segments, with a distinct but small head, and yellowish or dirty 

 white in colour. Osten Sacken's description of the larva of 

 Mycetophila may be drawn upon here. 



" A distinct horny head ; a fleshy labrura, encased in a horny 

 frame ; horny flat lamelliform mandibles, indented on the inside ; 

 maxillae with a large coriaceous inner lobe and a horny outside 

 piece, with a circular excision at the tip ; labium horny, small and 

 almost rudimentary ; body fleshy, with eight pairs of stigmata." 

 One pair of stigmata is on the first thoracic segment, the 

 remaining seven on the first seven abdominal segments. 



The larva possesses antennae, which in most genera are more or 

 less rudimentary, but in some (BolitopMla, for example, a non- 

 Oi-iental genus) they are distinctly jointed. In some genera ocelli 

 are present. The means of pi-ogression are furnished by rows of 

 short bristles on the under surface. Most of the larva? are 

 peripneustic* 



8ome species spin true cocoons when preparing to pupate, 

 whilst others construct a rude pupa-case from earthy materials. 

 Occasionally (Epicyj)ta, a European genus) the Inrval skin is 

 adapted to form a cocoon in which to pupate, but the pupa itself 

 is free. It is smooth, with more rounded corners than in the 

 TiPULiD.i;, the legs and antennae being generally distinctly 

 recognisable. 



Geogmphical Distribution. — World-wide, from the Arctic Circle 

 to the tropics in both hemispheres, but most abundant in 

 temperate regions. 



In comparing the Mycetophilid.e as a family with the other 

 families of x^bmatocera, it may be remembered that although the 

 SciARii^.E are usually ranked as a subfamily only of an equal 



* In at least one non-Oriental species, Nycetohia paUij)es,Mg., from Britain 

 and North Europe, the larva is ampbipnenstic, that is, it has a pair of stigmata 

 at the tail- end and a pair on the first thoracic segment. 



