St(n)lii/li.'iid(X' of the Amazon Valley. .SO.j 



to me one of the most characteristic of the South American 

 Stapkylinidai ; it has not yet occurred in Mexico or away 

 from the tropical parts of the South American continent, 

 and I know of no similar insects in the Old World. The 

 species here described show a considerable variation of 

 size, form and appearance, though some of them are ex- 

 cessively closely allied inter se. They are apparently very 

 rare, and I have had great difficulty in making up my 

 mind as to whether certain of the forms should be ti-eated 

 as species or varieties ; it is possible that I may in some 

 cases have come to wrong conclusions on this point, 

 although I have made a very careful examination in each 

 case before coming to a decision. 



1. TcBiiodema plana, n. sp. Nigra, capite, thorace, ely- 

 trisque feneis, abdomine segmentis 4°, 5°, 7°que ex parte 

 rufis ; thorace parce, irregulariter, dorso sub-biseriatim 

 punctato. Long. corp. 11 lin. ; lat. (elytrorum) 2 lin. 



, Antennas black, rather slender, nearly as thick at the 

 extremity as at the base, aboiit as long as head and thorax 

 (3 lines in length) ; 3rd joint nearly twice as long as 2nd, 

 11th slightly longer than 10th. Head distinctly narrower 

 than the thorax, with a large shallow impression on each 

 side in front; its surface with the middle and vertical 

 portions nearly impunctate, the impi-essions coarsely 

 ]nmctured ; some coarse scattered punctures behind the 

 labrum, and a few very coarse rugose punctures on the 

 inner side of the hind part of the eye ; besides the coarse 

 punctures the surface is sparingly sprinkled w4th some 

 minute punctures. Thorax about as long as broad, slightly 

 rounded at the sides, dark brassy, shining, sparingly and 

 rather finely punctured ; the punctures irregularly dis- 

 tributed, consisting of two longitudinal patches along the 

 middle separated by a broad irregular space, and outside 

 these Avith some punctures towards the sides, the front 

 part (behind the eyes) slightly raised and smooth; besides 

 the larger punctures with a few minute punctures, which 

 are most visible about the sides. Scutellum narrow and 

 elongate, with a few coarse pimctures. Elytra about as 

 long as, and scarcely broader than, the thorax, dark brassy, 

 with some coarse punctures scattered over them ; the hinder 

 external angles much rounded, and, as well as the project- 

 ing humeral angles, free from punctures. Hind body 



TRANS. ENT. SOC. 1876. — I'ART II. (jUXE.) X 



