Remarks on Some Fossils of the Cine inn ati Group. i 5 



imbricating plates of a somewhat triangular form, the whole some- 

 what resembling in appearance and character a loosely-arranged 

 jiine cone. 



Several detached plates of a fossil found in the rocks of the 

 Cincinnati Croup have been figured and described under the name 

 of PliimiilUcs Jaiiicsi, Hall and Whitfield. No perfect specimen 

 was known at the time these plates were described. The author, 

 however, having come into the possession of what seems to be a 

 perfect specimen, and believing it to belong, to another genus than 

 PliiiiiiiHtcs, has given it a new generic name with the following 



characters. 



LEPIDOCOLEUS n. g. 



Specimen sword shape, triangular in section having three un- 

 erpial sides, composed of two long rows of overlapping plates, 

 making a complete circumference. Ending of the upper extremity 

 rather sharp, at the base (?) or lower extremity having a very 

 short, rapid curvature towards the ventral side of the specimen. 

 The up])er row of i)lates has a very strong ridge or elevation near 

 the side where the two long rows of plates are joined the dorsal side, 

 which is nearly straight. The opposite long row of plates is 

 flat, and has a rapid, short curvature upon the edge of the straight 

 or dorsal side of the specimen, so as to meet the upper, or ridged 

 row of plates, and joined with it in zig-zag manner of overlapping 

 tiling, at one of the angles; and both meet each other like a knife 

 edge at the second angle or ventral side. At this side or angle 

 the specimen had the power of opening above the basal curvature, 

 to the upper extremity, while the third angle forms the ridge or 

 elevation of the upper long row of plates or ridged row of platest 



'Hie plates of both rows have the same form in outline, but 

 reverse to each other,and have the same markings as in PhimuUtes. 

 The i)lates have one long side from the apex, and a very short 

 side which slants more rapidly than the other side, being almost 

 straight down from the apex; they round off rather sharp on the 

 long side, are broad on the short side and very characteristic in 

 having scollops upon the long side 



LEPIDOCOLEUS JAIMESI, (Hall & Whitfield) Faber. 



Plate I, figures A. to F. — Magnified about 50 dia. 

 Specimen sword shape; triangular in transverse section, hav- 

 ing three unequal sides, composed of two long rows of overlapping 

 plates. The ridged row has fifteen overlapping plates, as shown in 



