6o 
BRITISH GALLS 
severely taxed to demonstrate any identity of the organs of 
the two instars.” 
The antennae are of great importance in the classification 
of Diptera. The majority of dipterous galls are caused by 
the Cecidomyidae or gall-midges, an extensive family of 
minute flies, remarkable in the rather long antennae, 
furnished with whorls of hairs; many writers have com¬ 
mented upon the beauty of these insects, and of the 
antennae of the males in particular. The larvae of all 
Cecids are not parasites on plants; some feed on dead 
animal matter, others prey upon Aphides and Mites, and 
some are cannibals. 
The peculiar spatula or anchor process which projects 
from the prothoracic segment in some species is probably 
used either for body movement, for perforating, or, in species 
provided also with horny papillae at the terminal segment, 
for causing the remarkable leaps executed by the larvae. 
The gall-midges are difficult to preserve, being so small 
and fragile; in spite of this they have received much 
attention, and about a thousand species have been described 
and named from various parts of the world. The original 
genus, Cecidomyia , has undergone much revision of late years, 
and has been split up into many genera, the chief being 
Asphondylia , Contarinia, Hormomyia , Oligotrophies , Perrisia 
(including many species at one time placed in the genus 
Dasyneuva ), Rhabdophaga , and Rhopalomyia. 
Before proceeding to describe some familiar dipterous 
galls, attention may be directed to certain curious pro¬ 
ductions which have been recorded as occuring on fungi 
on the Continent and in America. It seems desirable to 
bring them to the notice of British cecidologists, as but 
little is known respecting them at present. The first 
observation was published by Professor Boudier* in 1893, 
in a paper “ Sur les Causes de Production des Tubercles 
Pileux des Lames de Certains Agarics,” in which he records 
his discovery of minute oblong or rounded tubercles, about 
* See Rev. Gen. Bot. (Paris), vol. v., pp. 29-35. 
