22 COLEOPTERA. 



punctured. Aube says of his insect, " nitidissimus " — 

 " ititerstitiis planis, Icevibus/' and Kiesenwetter makes no 

 mention whatever of interstitial punctuation. It would 

 thus seem scarcely probable that Mr. Crotch's insects can 

 be identical with caspius, and the specimens Dr. Sharp 

 mentions as received from the Continent under the name of 

 distinctus would also appear irreconcilable with either that 

 species or caspius, on account of the punctuation of their 

 interstices. But the description of Mr. Crotch's specimens 

 appears to agree well enough with that of Erichson's 

 coli/vibus. 



The ^^ eli/tris apice fere recte truncatis" of Thomson's 

 hicolor seem very suggestive of caspius. 



16. Gyrinus colymbus, Er., Col. March., i, 191; Kies., 



1. c, 141 ; Ent. Ann., 1867. 

 Dr. Sharp, loc. cit., records six specimens in Mr. Crotch's 

 collection which he refers to this species, though apparently 

 with some little doubt, as they appear to be broader than 

 true colpnbus. He describes them as "ovate," with "the 

 interstices thickly and evidently punctured, almost trans- 

 versely strigose." Erichson states h\s cohjmbus to be oblong- 

 oval, with the interstices extremely finely punctured ; so 

 that it seems impossible to reconcile Mr, Crotch's specimens 

 with that species, with which, however, as above mentioned, 

 the caspius of Dr. Sharp, " oblong-ovate," " with the inter- 

 stices obsoletely punctured," is not unlikely to be identical. 



17. Gyrinus opacus. Sahib., Ins. Fenn., iv, 45 ; Ent. 



Ann., 1867. 



Dr. Sharp, loc. cit., quotes this species as local, but 

 common in Scotland, and also found at Horning in company 



