FOSSILS OF THE CUNTON GROUP. 563 



Telttnomya (Nucula?). minima, Foerste. 



J Plate 26, Figs 8 a, be; Plate 37, Figs. 13 a, b, c.) 



This form, first described in the Bulletin of Denisori Univ., Vol. I, 

 is represented by only a few specimens from the Beavertown marl at 

 Huffman's Quarry. They are all casts, and the following description 

 refers to these casts; A raised line extends along the tinge margin. 

 Along this, especially in the anterior lunule, one specimen shows 

 traces of transverse teeth, but whether the series is interrupted at the 

 beak or not is unknown. In the posterior lunule two lateral ridges 

 branch off from the median one. The posterior lunule has a lanceolate 

 outline, the anterior one is very broadly 'ovate. The shell is oblong, 

 much longer than high.' The convexity is most marked at the beak. 

 The leUgth of the largest specimen is 3.9 mm., the height is 2.7 mm., 

 and the thickness from valve to valve 1.9 mm. The beak is near the 

 anterior fourth of the cast. 



Tellinortiya {Nucula ?) socialis, sp. now 



(Pl_te37, Figs. 12 a, b, c.) 



The great majority of the minute lamellibranchs 'found in the 

 Beavertown marl at Huffman's Quarry, and in the corresponding layer at 

 Geo, Young's Quarry, on the Carrpllton Pike- west of Soldiers' Home, 

 belong to a species quite distinct from the last. All are casts. A raised 

 ,line extends along the hinge margin, and shows transverse teeth plainly 

 both in the anterior and in the posterior lunules, but whether the series 

 was interrupted at the beak or not could not be determined. The pos- 

 terior lunule has a lanceolate outline though narrower than in T. minima. 

 The anterior lunule is of almost linear outline, and this alone will readily 

 distinguish the two marl species. The form of the shell is also different — 

 being triangular oval. The convexity is most marked at the beak. The 

 largest shell is 3.5 mm. long, the height' is about the same, the thickness 

 is 1.9 mm. from valve to valve. The muscular impressions are well 

 shown, that of the anterior muscle being narrower.* 



Tellinomya (Nucuia?) Clintom nsis, sp. nov. 



(Plate 37, Fig. 15.) 



In the collections made by Prof. E. W. Claypole in the ferruginous 

 Clinton limestone near Mifflintown, Juniata Co., Penna., occurs a valve of 

 a decidedly nuculoid shell. Its precise generic relations could not be deter- 

 mined owing to the fact that the row of teeth is well shown only along the 

 posterior hinge line, and its interruption or continuation at the beak could 

 not be determined. In Middle Silurian rocks Tellinomya is however apt to 

 be a more common genus than Nucula, and hence the reference to that 



