BY THOMAS G. SLOANE. 369 



bidentate with ;i small projection just above base of second tooth. 

 Upper surface cyaneous. Length 8-5, breadth 2*9 mm. 



Carenum rectangulare, Macl. 

 Specimens of C. rectangulare, Macl., have been sent to me by 

 Mr. French as having been found between Alice Springs and 

 Charlotte Waters, Central Australia. These specimens I have 

 compared with the types of C. rectangulare, Macl., with which 

 they proved conspecific. They are intermediate between the 

 typical forms of C. rectangulare and C. tibiale, SI., and indicate 

 that C. tibiale should probably be placed under C. rectangulare 

 as a variety — the only differences being the less truncate base of 

 the prothorax and the more cordiform elytra of C. tibiale. The 

 colour of C. rectangulare is variable, one of Mr. French's specimens 

 having the elytra of a rich purple colour narrowly margined 

 with greenish-blue, and the prothorax purple near the sides, with 

 the margin coloured like that of the elytra. 



Table of Species of the C. smaragdidum Group. 

 A. Head with one supraorbital puncture, pro- 

 thorax with two marginal punctures on each 

 side. * 

 B. Prothorax with posterior angles strongly 

 marked. 

 c. Elytra with shoulders prominent, the 



base emarginate between them C. emarginatum, SI. 



cc. Elytra with shoulders rounded, the base 



hardly emarginate C. interioris, SI. 



BB. Prothorax with posterior angles rounded. 

 D. Presternum with intercoxal part widely 

 longitudinally channelled, truncate 

 at base. 

 e. Anterior angles of prothorax strongly 

 advanced. 

 f. Border of elytra hardly folded over 

 at humeral angles — not raised or 

 prominent (intermediate tibias with 

 a short external spur at apex) ('. ovale, SI. 



Excepting C. tumidipes, SI., which has three marginal punctures on each side. 



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