400 THE MEMBRANACEA. 



upon thistles throughout the summer. It measures 

 from one-eighth to one-sixth of an inch in length, and 

 the whole surface of the pro thorax and elytra, which 

 are of a greyish tint and greatly dilated at the sides, 

 appears to be composed of a network of numerous 

 small meshes, some of which, on the margins, are of a 

 brown or blackish colour, producing an appearance of 

 irregular spots. The prothorax, besides being thus 

 dilated on the sides, is produced in a triangular form 

 so as to cover the scutellum, and its surface exhibits 

 three very distinct little keels, of which the central 

 one runs from the anterior margin, which is a little 

 elevated above the head, to the apex of the scutellum- 

 like, produced portion of the thorax, whilst the two 

 lateral keels are much shorter. The hemelytra also 

 present two elevated keels, of which one runs parallel 

 to the outer margin, whilst the other passes at first 

 along the margin of the angular process of the pro- 

 thorax, and on reaching the apex of this, bends rather 

 suddenly, so as to meet the outer keel near the apex 

 of the hemelytron, thus enclosing a somewhat trian- 

 gular space on the disc of the wing. The membrane 

 is rather small, and of the same texture as the rest 

 of the organ. The head terminates in front in three 

 small points, and exhibits several still smaller spines 

 on its surface, and the antennae, which are rather 

 short, have the thick basal joint brown, the second 

 and third (the latter of which is thin, but nearly as 

 long as all the rest put together) reddish, and the 

 last joint black. The lower surface of the body is 

 black, as are also the thighs, but the tibiae and tarsi 

 are yellowish, with the minute claws which terminate 

 the latter, black. 



This little insect, curious as it is in its structure, is 



