BY REV. T. BLACKBURN. 239 



these slight differences in prothoracic sculpture are neither 

 specific nor sexual. The elytral interstices are perfectly flat in the 

 male. In the female they are nearly flat but not quite so abso- 

 lutel}' as in the male. The females moreover are a little narrower 

 and less rounded on the sides than the males. The size is : long. 

 44-6, lat. 3i-45- lines. The variation in colour is almost infinite, 

 but in all the examples I have seen the prevailing colour both 

 above and beneath is black. 



The form nigerrima, Germ., is widely distributed and is entirely 

 Vjlack except a red spot between the eyes and a little testaceous 

 colouring about the base of the antennte on the underside. Then 

 we find examples in which also the sides of the prothorax and 

 some spots on the alternate interstices of the elytra are red, then 

 examples in which also the lateral margins of the elytra are red 

 (and some in which the lateral margins are red without any spots 

 on the interstices), then examples [alternata, Germ.) in which the 

 prothorax is all black but the alternate interstices of the elytra 

 are entirely red, then examples (mentioned by Germar) differing 

 from alternata in having the sides of the prothorax red, then 

 examples {picta, Clip.) in which the prothorax is blotched with 

 red (or even more red than black) and the elytra bear red spots 

 not confined to the alternate interstices and even in extreme 

 varieties coalescing into large transverse blotches. I must admit 

 that in the last mentioned form the style of elytral marking is so 

 different from that of the other varieties as to suggest specific 

 distinctness, but I have vainly examined numerous specimens in 

 search of some constant structural difference. I have not seen 

 the form picta except from W. Australia. Specimens named 

 " nige7-rima " and ^^ picta," by Chapuis are before me. 



P. MENTITRIX, Sp.nOV. 



9. Sat late ovata; sat convexa; sat nitida; ut /•". rufobi'unnea, 

 Blackb. colorata, capite crebre subtilius punctulato; prothorace 

 fere ut P.rn/obritnnere sed angulis anticis acutis sat productis; 

 elytris 10-striatis, striis concinne (quam P. yemince, Clip, vix 

 minus fortiter; punctulatis, interstitiis planis (vel vix sub- 



