40 PROCEEDINGS OF THE NATIONAL MUSEUM vol-. 68 



HINDEODELLA LONGIDENS, new species 



Plate 8, figs. 14, 15 



General aspect as in the genotype H, suhtilis but bar somewhat 

 curved with much fewer, stronger, and longer denticles, all of which 

 are of subequal size, well separated from each other of one set 

 only, without alternation. Bar delicate and thin. 



Occurrence. — Mississippian (Hardin sandstone) : Mount Pleasant, 

 Tenn. 



Cotijpes.—Coit. No. 10988, U.S.N.M. 



HINDEODELLA RECTA, new species 



Plate 8, fig. 16 



Similar to H. longidens but the denticles are all much shorter, 

 the bar straighter and thicker and the anterior projection reduced 

 in length and carrying only a single denticle. The main cusp is 

 also relatively much smaller and shorter. 



Occurrence. — Mississippian (Hardin sandstone) : Mount Pleasant, 

 Tenn. 



Holotijpe.—C^t. No. 10984, U.S.N.M. 



HINDEODELLA ALTERNATA, new species 



Plate 1, figs. 14, 15 



In general aspect this tooth reminds considerably of H. longidens 

 but is readily distinguishable by its less curved bar, more uniform 

 denticulation and particularly by the presence of one or two shorter 

 and smaller denticles between each pair of the much more conspicu- 

 ous main sot. As the two sets are not exactly aligned, care must be 

 taken not to overlook the smaller set. 



Occurrence. — Devonian (Rhinestreet) : Shaleton, N. Y. 



Cotypes.—Q'j^t. No. 11300, U.S.N.M. 



HINDEODELLA DECURRENS, new species 



Plate 8, fig. 13 



Bar curved, the expanded anterior part bent downward and in- 

 ward and carrying three ridges or ribs rather than prominent denti- 

 cles. Similar ribs occur beliind the main denticle, which is large and 

 strong, and the rest of the bar is occupied by closely set alternately 

 large and long and much shorter minute denticles. This species 

 also suggests departure from the type species toward Eupmon- 

 iodlna but after detailed comparison the preponderant alliance 

 seems to favor Hindeodella. 



Occui^ence. — Mississippian (Hardin sandstone) : Mount Pleasant, 

 Tenn. 



Tlolotype.—Ciit. No. 10987, U.S.N.M. 



