DESCRIPTION OF SPECIES 323 



1905. BuUmorpha canaliculata Cumings and Beede, Department of Geology 

 and Natural Resources of Indiana, thirtietli annual report, page 1343, 

 plate 25, figure 41. 



Three imperfect specimens were collected. Two specimens lack the 

 tip of the apical coil and p^rt of the first coil, and one is slightly crushed. 

 The spire angle, 41 to 45 degrees, is the same as in B. canaliculata, and 

 in other respects the specimens agree with that species. 



PALEONEILO AMSDENEN8I8 n. sp. 

 Plate 19, figures 23-24. Text figures 1-2 



Twenty-five specimens, most of which 

 are fragmentary, are in onr collections. 

 All of the specimens but one have the shell 

 removed. In general outline the shell is / 

 subelliptical, but the posterior end is about ^ 

 two-thirds as wide as the anterior. Length 



of shell, about 17 millimeters; greatest figure l.— Enlarged Drawing of 



height at umbones, 9 millimeters; greatest Paieoneiio amsdenensis 



thickness directly below the Umbone, 5 shows ornamentation Enlarged 



•^ ' about 2l^ diameters. 



millimeters. 



The beaks are subcentral, but are slightly nearer the anterior end and 

 are directed toward the posterior end. Both extremities are gaping. The 

 posterior extremity is pinched and much thinner than the anterior. 



The shell is marked by unequally spaced growth lines, which are crossed 

 by very fine irregular lines that radiate from the beaks and are most 

 prominent on the umbones. The specimen that retains the shell is the 

 only one that has these lines preserved. A short external ligament was 

 present. 



The dentition is taxodont and not interrupted below the beaks. The 

 teeth are longest at the beaks and broadest behind the beaks. About 16 

 teeth are present and the number is about the same in front and behind 

 the beaks. 



Musculature obscure in the types. 



Our specimens resemble Girty's figures of Yoldia glabra,^ but the radi- 

 ating lines are not mentioned in descriptions or shown in figures of that 

 species. The dentition differs, as shown in plate 19, figure 24, of this 

 paper, and plate 13, figure 9a of Girty's paper. Evidences of an external 

 ligament are clear in our species and are doubtful in Girty's. 



^ Fauna of the Wewoka formation of Oklahoma, pi. 13, figs. 9-15. 



