BY REV. T. BLACKBURN. 685 



P. POSTiCALis, Blackb, 



AVitli this species commences what I regard as the second of 

 two aggregates into which I regard this subgroup as naturally 

 divisible, although the exigencies of tabulation have not enabled 

 me to treat them as primary divisions. The species of the sub- 

 group now remaining to be dealt with are all of small size and 

 are distinguished by the great width of their head and the short- 

 ness of the basal joint of their antenna?, which is more or less 

 depressed and of piriform or subtriangular form (sometimes more 

 or less claviform) and with its greatest width not (or not much) less 

 than its length, its apex with a more or less marked tendency to 

 be obliquely truncate. The objection to making these characters 

 primary ones in a tabulation lies in the fact that they are found to 

 a certain extent in a few of the comparatively large species (e g., 

 Hera and suturalis) in the earlier part of the subgroup. The 

 species having these characters of the head and antennae are 

 easily subdivided again into two aggregates, in the former of 

 which the prosternum is normal and the 6th joint of the antennae 

 (or even the 5th) is the 1st of the compressed and dilated joints, 

 while in the latter the middle part of the prosternum is con- 

 tinuously convex with the lateral carinas more or less obsolete 

 and never elevated to the level of the actual middle line, and 

 the 7th joint of the antennte is the 1st of the dilated joints. The 

 former of the two aggregates just mentioned (i.e., that with the 

 prosternum normal) is again divisible into two sections, in the 

 former of which the punctures of the elytral interstices are of 

 equal size (or nearly so), while in the latter these punctures are 

 of very unequal size (especially in the lateral interstices), there 

 being on, at any rate, some of them a row of punctures in single 

 file much larger than the ordinary interstitial punctures, in some 

 species as large as the seriate punctures. 



The present species then commences the 1st of the three 

 aggregates indicated in the above remarks, distinguished from 

 the species preceding it by the absence of the strongly marked 

 •characters (indicated in the tabulation) and of the comparatively 



