SYNOPSIS OF THE ORTHOPTERA OF WESTERN EUROPE. 317 



Table op Genera. 



1. Antennae with 16-30 segments. (2nd tarsal segment cylindrical). 



2. Elytra and wings perfectly developed . . . . . . . . Labiduea. 



2.2. Elytra absent or rudimentary ; wings absent . . . . Anisolabis. 



1.1. Antennse with from 10-15 segments. 



2. Second tarsal segment cylindrical . . . . . . . . Labia. 



2.2. Second tarsal segment heart-shaped. 



3. Forceps (? broadened and flattened at base. (Elytra 



perfectly developed ; wings usually so) . . . . . . Forficula. 



3.3. Forceps <? remote at base, slender. 



4. Wings and elytra perfectly developed . . . . Anechura. 



4.4. Elytra developed or rudimentary ; wings always 

 absent. 

 5. Slender insects ; abdomen not dilated. Forceps 



slender . . . . . . . . . . . . Apterygida. 



5.5. Stout insects; abdomen dilated towards apex; 



forceps more or less stout . . . . . . Chelidura. 



Genus 1 : Labidura, Leach. 



This genus is widely distributed throughout the world, and the 

 two species occurring in Europe are now cosmopolitan, although 

 probably Palfearctic in origin. 



It is characterised by the large number (16-30) of segments in the 

 antennae, the presence of entire elytra, and usually also of wings, by 

 the absence of lateral tubercles on the 2nd and Brd abdominal seg- 

 ments ; the forceps of the male are separated at the base, not flattened, 

 gently incurved, armed, usually on the inner margin, with a varying 

 number of teeth. 



The two species are hardly to be confused. L. ripan'a is large and 

 very pale in colour ; L. (Jufourii is very considerably smaller, it is 

 dark in colour, and entirely distinct in appearance. 



Labidura riparia, Pallas ( = (iiga7itea, Fabr. et auctt.). 



Easily recognisable by its large size and pale colour. Length of 

 body: lBmm.-19mm., ^, $; of forceps, 6*1 1mm., ^ ; 4-6mm., $. 



It occurs throughout the coast of southern Europe, and also on river- 

 banks ; it may be found under stones and refuse, especially in sandy 

 places. In England, it is found in several localities on the south 

 coast, but is a great rarity. In France, it is common enough on the 

 south coast, and has occurred as far north as Brittany ; also on the 

 river Allier near Moulins, in the centre. In the interior of Europe it 

 has been taken near Geneva ; in Germany in Silesia and Saxony, 

 Thuringia, and near Berlin. It is common enough in Spain and 

 Portugal in suitable localities ; in Austria on the Prater, near 

 Vienna. 



It is extremely variable in size and colour ; the wings and also 

 teeth of the forceps may be absent, and the colour very dark, some- 

 times almost black. 



Labidura lividipes, Dufour( = r/*(/b»r//, Desm. = meruHonalis, Serville). 



Considerably smaller than the last ; hinder border of pronotum 

 rounded instead of straight ; colour dark. Length of body : 8-9mm., 

 3' , $ ; of forceps, 2-3mm., 3^ , 2 . 



It occurs in damp places in the extreme south ; in Spain it is met 

 with on the coast of the Mediterranean ; the variety nn'na, Lucas, 

 with unarmed forceps in the S , is recorded from Chiclana ; Desmarest 



