176 Rev. H. Clark on the Mexican Species of Hydropori. 



obsolete stria at the base of the elytra. At first sight the species 

 might be taken for large and dark specimens of H. convexus, Aube 

 (found in the States) ; it is, however, an entirely separate species. 

 In the collections of the British Museum, Mr. Fry, and the 

 Rev. H. Clark. 



2. Breviter ovati. 



4. H. Roffii, n. sp. 



H. latus, robustus, impubescens, punctato-striatus, niger ; elytris ad 

 basin rufo notatis, ad apicem juxta marginem rufo maculatis, pedi- 

 bus fuscis. 



Long. corp. 2 lin., lat. 1 lin. 



Ovate, broad, robust, impubescent, punctate-striate, black, 

 the base and apex of the elytra being frequently rufo-maculate : 

 head broadly transverse ; when seen from the front, two distinct 

 depressions are apparent on either side near the inner surface of 

 the eyes ; under a high power the surface is finely punctate, 

 the apex and line of the base being more or less distinctly 

 marked with rufous : thorax broadly transverse, the sides slightly 

 rounded and much constricted towards the front ; the surface is 

 subglobose ; parallel to the anterior and also the posterior mar- 

 gin is a depressed line of punctures, those at the base being 

 more distinctly apparent : elytra broad, attenuate towards the 

 apex, subglobose, with three distinctly impressed rows of stria?, 

 and a few single deep punctures near the line of the base be- 

 tween the first and second stria? ; the surface (when seen under 

 a high power) is very finely granulated, in colour black, the line 

 of the base being marked with rufous (in some examples this 

 basal marking is almost obsolete) ; towards the apex, near the 

 margins, are two or three well-defined red spots ; the apex itself 

 also is distinctly marked with red : abdomen and underside black : 

 legs fuscous : antenna, rufous, the apical joints being rufo- 

 fuscous. 



Var. A. The elytra in colour entirely black ; in all examples, 

 however, there is an indication, however faint, of rufous colouring 

 at the apex. 



Several examples before me of this species from M. Truqui's 

 collection exhibit every shade of coloration, from the typical 

 pattern to the almost black variety. 



In the cabinets of the British Museum, Mr. Fry, and the 

 Rev. Hamlet Clark. 



5. H. decemsignatus, n. sp. 



H. ovatus, ad apicem attenuatus, punctato-striatus, niger ; elytris 



flavo decemnotatis ; antennis testaceis ; pedibus fuscis. 

 Long. corp. 2 lin., lat. 1 lin. 



Broadly ovate, compressed and attenuated towards the apex, 



