218 Mr. J. Walton on the pemis Trachyphloeus. 



is synonymous with Tr. scaber ; however, in deference to the great 

 authorities above named, it is necessary to show better reasons 

 for venturing to dissent : according to Schonherr, " Cure, tessel- 

 latus of Marsh, (from an examination of British specimens) differs 

 from Cure, seabriculus by having the thorax equal, neither eanali- 

 culated nor impressed ; the elytra more globose and deeply punc- 

 tate-striate^ ." According to Germar, " Tr. scaber of Linn. [Cure, 

 tessellatus of Marsh.) has the thorax obsoletely canaliculated and 

 hifoveolated posteriorly; the elytra ovato-globose and punetate- 

 striate ; it is very like Tr. bifoveolatus, and differs almost only by 

 its shorter elytra, the greatest breadth of which is in the middlef." 

 '^ Tr. seabriculus has been sent to me by Schonherr himself, and 

 to it Cure, bifoveolatus of Beck belongs ; it has the thorax with 

 scarcely any central furrow, and the elytra scarcely exhibit strice, 

 and its greatest breadth is beyond the middleX'" 



Nevertheless the whole of my denuded specimens, and also the 

 four examples of Cure, bifoveolatus sent to me by Germar himself, 

 have the thorax more or less unequal, distinctly bifoveolated and 

 furrowed ; the elytra ovate, more or less convex, gibbous beyond 

 the middle, and very distinctly punctate- striate ; as to the form of 

 the elytra it is subject to variation, and has a tendency, especially 

 in large and in fully matured specimens, to become more convex, 

 and varies from ovate to globose-ovate : this insect agrees in all 

 its essential characters with the excellent description of Cure, 

 seabriculus by Gyllenhal ; but he very justly observes, that unless 

 the upper surface is denuded, the sculpture is scarcely percep- 

 tible. 



Of this species it may be useful to notice, that the inequality 

 and the sculpture of the thorax, above and at the sides poste- 

 riorly, have a most extraordinary range of variation, and although 

 it is constantly more or less distinctly canaliculated, bifoveolated, 

 and closely and minutely granulated or rugulose-punctate, yet 

 in the major part of my specimens, these characters are inter- 

 spersed with a greater or less number of scattered acute tubercles, 

 or rugged with short ridges or tubercles, whilst in others they 

 are obsolete or entirely absent : it may be distinguished from every 

 other species by having the head invariably with a transverse 

 striga or constricted at the base, and by the anterior tibiae being 

 armed in both sexes at their apices, externally and in front, with 

 six minute spines, which hitherto, as far as I know, have not been 

 noticed. 



I intend ultimately to deposit in the cabinets of the British 



* Syn. In3. Suppl. vii. p. 114. 



t Germ. Stett. Eut.Zeit. 1842, p. 102. + Ibid. 



