7?^ CANARIAIf COLEOPTERA. 



towards the apex of each of its elytra, the present Hydroporus, 

 although abundantly distinct therefrom, is somewhat allied to the 

 Eui'opean H. assimilis, Payk. ( =f rater, Aube). It is however rather 

 larger, paler, and less ovate than that insect ; its prothorax is rela- 

 tively narrower, proportionally a little shorter, more equally rounded 

 at the sides, rather more produced in the contra behind, and with its 

 basal patches more transverse and but seldom suffused into the 

 blackened posterior margin ; and its elytra are less convex, more 

 straightened laterally, and with their darker lines very much more 

 broken and anteriorly abbreviated. It appears to be closely related 

 to the H. affinis, Aube, from Sardinia ; nevertheless I am assured by 

 Dr. Schaum that he considers it truly distinct from that species (of 

 which he has lately examined " several authenticated specimens "). 

 It was taken abundantly by Mr. Gray and myself at La Antigua in 

 Fuerteventura, during January 1858 ; and during April of the fol- 

 lowing year I met with it, in still greater profusion, in the Rio 

 Palmas of the same island. It occurs also in the south of Spain, 

 ha\'ing been captured at Malaga, by Messrs. Gray and Clark, in May 

 of 1856. The Spanish examples are a trifle smaller than the Cana- 

 rian ones. 



123. Hydroporus Ceresyi. 



//. oblongus, subconvexus, supra testaceus, subtiliter pubescens ; pro- 

 thorace sequali, ad latera oblique subreeto, postice in medio pro- 

 ducto necnon utrinque macula parva indistincta suff'usa ornato ; 

 elytris subparallelis, pallide testaceis, lineis nigris plus minus in- 

 tegris ornatis. — Long. corp. lin. l|-2. 



Hydroporus Ceresyi, Ai(be, Hydrocanth, 543 (1838). 



Habitat Lanzarotam, in lacu illo salino " Januvio " dieto captus. 



I do not hesitate to refer this Bydrojjorus to the II. Ceresyi of 

 southern Europe, even though the Canarian examples now before me 

 do not perfectly accord with types in my collection from Crete and 

 the south of France ; for their discrepancies inter se are so slight as 

 to be but just appreciable ; and moreover it is the opinion of Dr. 

 Schaum that they cannot be treated as distinct. Nevertheless it 

 appears to me that the prothorax of the Lanzarotan individuals is 

 a trijie wider (being quite as broad behind as the base of the elytra) 

 and perhaps a little more rounded at the edges, and also that their 

 elytra (the testaceous portions of which are usually of a darker or 

 more rufescent hue) are somewhat straighter at the sides — causing 

 the entire insect to seem, if anything, rather more oblong : however, 

 I do not believe that they can be regarded, at the utmost, as more 



