28 CATALOGUE OF 
%%& Fore femora unarmed. - c - - ANDROGEUS. 
tt Three exterior veins of the membrane joined by 
the transverse veinlet. é - = LetHe@us. 
The following Synopsis is an abbreviated translation of Fieber’s 
arrangement of the European species of the family. 
A, Antenne 3-jointed. - - - - TRITOMACERA. 
B. Antenne 4-jointed. 
a. Fore auxiliary segments in the middle of the 
discal segments. - -  IscHNODEMUS. 
b. All the auxiliary segments faeorted by tte hind 
borders of the discal segments. 
Hooks of the areolets distinct. 
Hooks on the lower veins. Veins of the mem- 
brane springing from its base, the two inner 
veins from one areolet, or all the veins free. 
} First joint of the hind tarsi much longer than the 
second and third joints together, rarely 
equalling them in length. 
§ Prothorax in front with two transverse #-forming 
furrows. Membrane with one areolet at the 
base of the two inner veins (Lygeidea). 
* 
ast 
x Eyes truncated behind. - - - TETRALACCUS, 
x xX Eyes not truncated behind. 
o Rostrum longer than the head beneath. - - Lyczvs. 
oo Rostrum as long as the bead beneath. 
—+ Fore femora with a little subapical spine. - C £NocoRIS. 
—+—+ Fore femora unarmed. 
++ Head transverse. First joint of the hind tarsi 
as long as the second and third joints together. AROCATUS. 
++++ Head as long as broad. First joint of the hind 
tarsi longer than the second and third joints 
together. 
« Scutellum in the middle with lateral furrows.  - LyYG#0sSoMA. 
torm Scutellum without furrows. - - - NysIus. 
§§ Prothorax in front without transverse furrows, 
Membrane with four or five longitudinalstraight 
or curved veins. 
x Prothorax contracted behiud the middle; sides 
tumid. (Plociomera). 
o Prothorax much longer than its hind border. - PaRroMIus. 
oo Prothorax as long as the breadth of its hind border. PLocromErus. 
XX Prothorax not contracted, or with the hind part 
contracted beneath. 
o Sides of the prothorax obtuse or concise. 
—+ Sides of the prothorax without keels. 
++ Prothorax elongated. 
« Rostrum extending to the propectus.  - - PRoDERUS. 
cour Rostrum extending to the middle of the mesu- 
pectus. - . = - - Icus. 
++++ Prothorax trapeziform, short. 
