CALANDRID AiI—COSSONIN Z—COSSONINI. 155 
considerably larger than either of those described below or than the Aix 
species, C. marionii Oust., which is midway in size between ours; but all 
of them, and notably the Aix species, have a much longer beak than either 
of ours. In general, but in a vague way, our C. gabbii most nearly resembles 
C. spielbergii; our other species can hardly be compared with any one of 
the European fossils, all of which, it seems to me, require renewed exami- 
nation. The Aix species in particular with its long and slender snout and 
very arched body can hardly be regarded as a Cossonus. 
Table of the species of Cossonus. 
4 3} D 
Body more than four times as long as high, contracted at base of elytra; beak less 
than twice as long as broad; eyes oblique, anterior ........-.-.---------- rutus. 
Body less than three times as long as high, not contracted at base of elytra; beak 
fully twice as long as broad; eyes transverse, median..............------ gabbii. 
Cossonus RUTUS. 
= TNE nh 
Blan Hie. 7 
A rather stout-bodied form with short and stout beak. Head and pro- 
thorax together forming without the beak a perfect half-oval, the beak 
about as long as the head and hardly twice as long as broad; eyes moder- 
ately large, more than half as long as the breadth of the beak, round-oval, 
oblique, the facets almost exactly 0:02" in diameter; head smooth. Pro- 
thorax fully half as high again as long, bluntly subrugose and very finely, 
faintly, and shallowly punctate. Elytra very finely and bluntly scabrous, 
broadly arched with faintly granulate, slightly elevated, slender carinie, 
the pygidium apparently covered. 
Length exclusive of beak, 4™™; height, 1:5™"; length of beak, 0-55". 
Roan mountains, western Colorado, uppermost layers. One specimen, 
Nos. 945 and 946, U. 8. Geological Survey. 
COSSONUS GABBII. 
Exe, hiss tt 
A slender, regular, oblong obovate form with rather short beak. Head 
moderately large, regular, apparently with the same sculpture as the pro- 
