] 82 [August, 



tion was communicated in that state to Canon Fowler. He also was 

 much troubled by the small species of the genus, and his book on 

 " British Coleoptera " expressed a very uncertain opinion about them. 

 Some fifteen or twenty years ago I commenced an examination of the 

 sedeagus in this genus, but pressure of other work did not allow me 

 to continue the study. I have now, however, found time to complete 

 it, and the results will be stated in the notes, of which this is the first. 



The larger and metallic species of the genus are easily dealt with, 

 and are comparatively few in number. The smaller, brown or blackish 

 species are really difficult to discriminate, and the Continental, as well 

 as the British literature, is imsatisfactory. The sedeagus does not 

 present remarkably different characters ; the lateral lobes are similar 

 in all the species, but the median lobe, or body of the organ, presents 

 characters which, though slight, are extremely valuable, so that by 

 their aid I have been able to discriminate the species in a satisfactory 

 manner. And I find that this group includes nine British species, or 

 if we include the brown variety of 0. azureus, ten species. This is an 

 addition of four species to our catalogue. As I shall have occasion to 

 use their names in my comparisons, I had better here mention them 

 all. They ai'e : 1, brevicollis, Dej. ; 2, rvfibarbis, Fabr. ; 3, cordahii<, 

 Duftschm. ; 4, rit/picola, Sturm ; 5, rupicoloides, sp. n. ; 6, championi, 

 sp. n. ; 7, parallelus, Dej. (?) ; 8, rectangulus, Thoms. ; 9, imncticollis, 

 Payk. ; 10, azureus, Fabr. var. similis, Dej. 



The group does not lend itself satisfactorily to tabulation, the 

 species being very closely allied, and some of them variable. So far 

 as our British forms are concerned, the sedeagus divides them fairly 

 well into two groups: (1) the aedeagus terminates as a blunt point; 

 this includes only hrevicollis, cordatus, and rufiharhis, and the latter is to 

 some extent transitory to the second division ; (2) in which the sedeagus 

 terminates by a raised margin, which when very strongly expressed, 

 projects a little on each side in the form of a sharp angle. This divi- 

 sion is not a sharp one, as in point of fact each species differs a little 

 from the others in the shape of the tip. But in addition to this the 

 organ presents important differences in length, calibre, curvature, 

 torsion, the thickness of the apical portion, and the extension of the 

 median orifice towards the tip. These characters are nearly, but not 

 quite, constant in each species ; and when a detennination is made by 

 their aid it is found that the result is also satisfactory as regards the 

 body characters. The species can in fact be discriminated without the 

 aid of the sedeagus, though the student will, I hope, not be satisfied 



