BY JOHN WALTON. 7 



of various kinds ; specimens from the former were always darker 

 than others. Until there is a difference discovered in the habit, 

 and a specific character, of sufficient weight or consequence, in 

 the sculpture, I shall regard them all as one variable species. 

 Mr. Stephens thinks, that P. ccesius may be a mere variety, or 

 the opposite sex of P. Pi/ri. I am convinced that P. ccesim 

 and P. Alneti are identically the same species ; for these and 

 the above reasons, I have united them all under the Linnoean 

 name of P. Pyri. 



P. macuUcornis. — A very distinct northern species, taken by 

 me in Yorkshire : in the habit and sculpture, when examined, it 

 will be found to be very different from P. argentatus, its nearest 

 congener ; there is also a good character in the second joint of 

 the funiculus of the antennae, it is shorter and stouter than in 

 the following insect, the two first being of equal length, whereas 

 in the following species (being the only one with which it can 

 be confounded), the second joint is longer and more slender 

 than the first of the funiculus, therefore of unequal lengths. 



P. argentatus. — There is in this species and the preceding a 

 very singular and very remarkable variation to be noticed in 

 the form of the thorax : the females (for I have taken both 

 species in coptild) have the sides of the thorax considerably di- 

 lated at the middle, and gibbous on the disk, giving it a globose 

 appearance ; the small varieties have the thorax subcylindrical ; 

 the colour of the legs and antennae are more or less dark, 

 regulated by the situation in which they are found ; there is 

 also another character, in this and the preceding species, 

 worthy of notice, — they are often taken with powerful dentated 

 mandibles, projecting from the apex of the rostrum, a character 

 which gives them the appearance of a Cicindela. I have observed 

 other species in this genus as well as in Polydrusus, with exerted 

 mandibles, some simple and others dentate ; from w^hich I infer 

 it is a general character in these nearly allied genera. 



P. Pomonw is a variety of P. uniformis. 



P. uniformis is a distinct species, dissimilar in habit to P. 

 parmihis ; the abdomen beneath is densely clothed with scales, 

 nearly to the apex. 



P. albidus is a variety of P. uniformis. 



P. parvulus, a variable but distinct species ; the abdomen 

 beneath is pubescent, and piceous or testaceous at the apex. 

 I have taken numerous pairs of this and P. uniformis, in copida, 



