NATURAL SCIENCES OF PHILADELPHIA. G9 



were originally referred to that genus is to be regarded as the 

 typical form of the same, and something can be known in regard 

 to the hinge and internal characters of those shells, it seems to 

 me almost impossible to determine what Sanguinolites is. I do 

 not agree with those, however, who would make AUoinsma of 

 King a synonym of Prof. McCoy's genus, though some of the 

 species included by him may belong to AUorisma. 

 Locality and position. Same as foregoing. 



SANGUINOLITES ? OBLIQTJTJS, Meek. 



Shell SO depressed and elongated as to be nearly three times as 

 long as high, rather distinctly convex, particularly along the 

 posterior umbonal slopes, which are more or less angular from 

 the beaks nearly to the posterior basal extremity ; pallial margin 

 very flearly straight along most of its length ; anterior end ex- 

 tremely short, and a little sinuous on the upper side just in front 

 of the beaks, the sinuosity being caused bj- a ver}^ small deep 

 lunule, at the lower end of which the margin is a little projecting 

 and subangular in outline, and from this little iDrojection curves 

 obliquely backward into the base ; cardinal margin extending 

 back about three-fourths the length of the valves, and inflected so 

 as to form a well-defined, lanceolate escutcheon along its entire 

 length ; posterior side narrowed with a long slope above from the 

 end of the hinge to the extremity-, which is a little gaping and very 

 narrowly rounded or almost angular below ; beaks strongly de- 

 pressed, very oblique, compressed below the ridges, \Qvy nearly 

 terminal, and with the immediate points incurved over the little 

 lunule. Surface showing only lines and furrows of growth, with 

 occasional small, obscure, concentric wrinkles, that are not regu- 

 larly arranged. 



Length, 2.13 inches; height, O.tT inch; convexity, O.tO inch. 



This species seems to be nearly related to a form from the same 

 rock at Medina, Ohio, specimens of which were loaned hy Dr. 

 Newberry to Prof. Hall, some time back, and returaed with the 

 name Sanguinolites eeolus attached. A careful comparison, how. 

 ever, of good specimens of each, shows them to be clearly distinct; 

 the form under consideration being much more convex along tiie 

 umbonal slopes, which are also more angular. Its beaks likewise 

 differ in being decidedly more nearly terminal, and the inflection 

 of its cardinal margin wider. The specimens of S. seohis also 

 1871.] 



