DYTISCIDjE. 67 



Apparently peculiar to Madeira proper, where it occurs in the 

 streams at most elevations. 



201. Hydroporas tessellatus. 



Hydroporus tessellatus (Dej.), Aube, Hydrocanth. 516 (1838). 

 "- , Woll, Cat. Can. Col 79 (1864). 



Habitat Canarienses (Can., Ten., Gom., Palma), in rivulis vulgaris. 



This species would seem to represent at the Canaries the H. vigi- 

 lans, of Madeira; and it is equally abundant wherever there are 

 streams. In the two eastern islands, however, of the Group it has 

 not yet been observed ; and the absence of water in Hierro has pre- 

 vented its being detected there. But in Grand Canary, Teneriife, 

 Gomera, and Palma it is common, at nearly all elevations. 



Genus 50. LACCOPHILUS. 



Leach, Zool Miscell iii. 69 (1817). 



202. Laccophilus inflatus. 

 Laccophilus inflatus, Woll., Cat. Can. Col. 79 (1864). 



Habitat Canarienses (Can., Ten., Gom.), in aquis hinc inde haud in- 

 frequens. 



A Canarian Laccophilus, which has been observed hitherto in Grand 

 Canary, TenerifFe, and Gomera. Although differing a little from 

 both of them, it is not impossible that it may be in reality a geogra- 

 phical modification of either the minutus or hyalinus of more northern 

 latitudes ; but as the acknowledged distinctions between so many 

 allied species in these groups of the Hydrocantharidm are extremely 

 slight, I think that the L. inflatus has at least as much claim for 

 separation as many other forms which are universally recognized. 



Genus 51. COLYMBETES. 



Clairville, Ent. Helv. ii. 198 (1806). 



203. Colymbetes coriaceus. 



Dytiscus coriaceus, Hoffm. in litt. 

 Meladema coriacea, Lap., Etud. JEnt. 98 (1834). 

 Colymbetes coriaceus, Aube, Hydrocanth. 220 (1838). 

 Dyticus coriaceus, Bridle, in Webb et Berth. (Col) 58 (1838). 

 Colymbetes coriaceus, Woll, Cat. Can. Col 80 (1864). 



Habitat Canarienses (Can., Ten.), in aquis prassertim fluentibus sat 

 frequens. 



