146 Descriptions of British Diptera. 
English and Irish Diptera, and again earnestly request additional 
information respecting Species and Localities, which will either be 
introduced in the proper places, or added as supplements to the 
parts which may be previously published. The species which have 
been found in Scotland are distinguished by a small s. after the 
specific name. The next paper will include the Tabanidce. EDS.) 
ORDER DIPTERA, 
FAMILY STRATIOMYD^, Latr. 
THE family group of two- winged flies, distinguished by the above 
name, have the antennae porrect, approximating at the base, and 
composed of three joints, the third, or terminal joint,, divided into 
rings by means of faintly marked incisures. These organs are ge- 
nerally furnished with a style or an elongate seta at the extremity. 
The proboscis is short, the labella alone being exserted. The ocelli 
are three in number, and placed in the form of a triangle usually on 
the crown : abdomen oval, generally wider than the head, and flat or 
slightly convex, composed of five segments; wings when at rest over- 
lapping each other, and lying along the back of the abdomen, leaving 
the sides of it exposed, and projecting beyond the apex. The typi- 
cal genera are rather of obscure colours, having the sides of the body 
ornamented with light-coloured spots and abbreviated bands. The 
species frequent marshy places, and the larvae, in most instances, 
are aquatic. The indigenous genera admit of being distinguished 
by the following concise external characters : 
. * 
Istjointmuchlonger than the 2d ..... STRATIOMYS. 
lst and 2d ^ ? ^ ........ DO _A. 
with an elongate ) 3d joint 4-ringed ....................... OXYCERA. 
. ....................... . 
style; 3 - 5-ringed ....................... CLITELLARIA. 
Scutellum un- 1 ,. * 7 abdomen somewhat globular ......... PACHYGASTER. 
armed; 3d ( OT ar; } -- oblong ....................... SARGUS. 
joint of the ( ovate ................................................. CHLOROMYIA. 
antennae 3 subfusiform ............................................ NEMOTELUS. 
GENUS STRATIOMYS, Geoftroy. 
Antennae rather longer than the head, directed forwards, approxi- 
mating at the base, the third joint diverging obliquely ; the first 
joint elongate and cylindrical, the second short and cup-shaped, the 
third very long, subfusiform, divided into five distinct rings, and 
without a terminal seta, (Fig. 1 :) proboscis short ; the labru n li- 
near, corneous, notched in fro.it ; (Fig. 26;) palpi three-jointed, 
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