CANARIAN COLEOPTER.V. tO 



Before closely examining- this Haliplus I had regarded it as iden- 

 tical with the common European //, lineatocoUis, to which iu general 

 coloui'ing and aspect it is very nearly allied. Considering, however, 

 the smallness of the characters which constitute specific ones in the 

 Hydradephaga, I am satisfied that it cannot be referred to that insect ; 

 and such is likewise the opinion of Dr. Schaum. It is not only 

 slightly larger, wider, and more oblong (the head, thorax, and elytra 

 being eacJi of them relatively broader, and the entire outline some- 

 what more parallel), but the blacker portions of its surface are more 

 developed and suffused, and the punctures of its striae are smaller 

 and more numerous, — whilst (on the contrary) those of its pro thorax 

 are perhaps coarser. This last, also, is of a slightly difi'erent shape, — 

 being less narrowed anteriorly, rather less obliquely-straightened at 

 the sides, and perceptibly wider behind (where it exceeds in breadth 

 the extreme base of the elytra), and with its two curved fovese deeper. 

 The only islands in which I have observed it hitherto are Grand 

 Canary and Gomera ; in the latter of which it was taken abundantly 

 by Mr. Gray and myseK, in the valley of San Sebastian, during Feb- 

 ruary 1858, and subsequently by Dr. Crotch near Hermigua ; whilst, 

 in March and April of the same year, I found it in the district of 

 El Monte of the former. 



Genus 40. HYDROPORUS. 



Clairville, Ent. Helv. ii. 183 (1806). 



115. Hydroporus musicus. 



Hydroporus musicus, Kltiq, Si/mb. Fhys. pi. 33. f. 12 (1829). 

 , Aube, Hydroc'anth. 475 (1838). 



Habitat in aquis Canarice Grandis, rarissimus. 



The only island in which I have hitherto observed this Hydroporus 

 is Grand Canary ; where, however, it appears to be scarce. I pos- 

 sess examples taken by Dr. Schaum in Egypt ; but the Canarian ones 

 are a trifle rounder and more convex, as also of a somewhat less 

 pallid hue. 



116. Hydroporus confluens. 



Dytiscus confluens, Fah., Ent. Si/st. i. 198 (1792). 

 Hydroporus confluens, Aube, Hijdrocanth. 557 (1838). 



, Wall., Ins. Mad. 87 (1854). 



, Id., Cat. Mad. Col. 27 (1857). 



Habitat in Fuerteventura et Gomera, minus frequens. 



This insect, which occurs throughout Europe and the north of 



Africa, and which is imiversal at the Madeiras, appears to be some- 



