CLINTON, LOWER nKLDERBEHG, CHEMUNG, AND WAVERLY GROUPS. 45^^ 



Fcyrmation and localilij. Chemung gi'oiip, north of Blacklog creek, Orbisonia, 

 Huntingdon county, Pennsylvania. 



TELLINOMYA (PAL.EONEILO) CUNEATA Simpson, n. sp., Fi^L'. 21. 



Shell small, ovate cuneate in outline; length twice the height; basal margin 

 broadly rounding, becoming constricted or arcuate at about one-third the length of 

 the shell from the antei'ior end; posterior margin short, obliquely t*-. 

 truncated; cardinal line essentially straight, sloping at nearly the ^j ^ ' '''w 

 same angle anteriorly and posteriorly to the beaks ; anterior end 

 large and regularly rounded. 



Greatest convexity of the valves above the middle nnd in the umbonal rcirion. 

 Beaks about central, slightly incurved, extending a little above the hinge line ; um- 

 bonal ridge clearly defined, subangular ; posterior slope declining regularly aiid 

 abruptly to the cardinal line, lielow the umbonal ridge there is a broad shallow 

 depression, extending from near the beaks to the base and constricting the basal 

 margin. 



Surface marked by strong, lamellose, concentric stria? at regular distances apart, 

 and by very fine concentric lines between the lamellose striic. 



On the specimens observed there are eight or nine transverse teeth on each side 

 of the beak. 



The specimens measured have a length of 12 mm., and a height of G mm. 



This siiecies may be distinguished from T. (P.) dimimtens of this formation by 

 its smaller size, more distinct lamellose striations and the less abrupt constriction of 

 the posterior portion. 



Formation and localitij. Clinton group, seven miles north-west of Lewistown, 

 Mifflin county ; and north of Blacklog creek, Orbisonia, Huntingdon county, Penn- 

 sylvania. 



TKLIJNOMVA (PAL/EOXEILOi DIMINUENS Simpson, n. sp., Fi-. 22. 



This species is very similar to the preceding, but is usually larger, the specimens 

 obsei-ved having a length of from 23 to 2.j mm., and a . 

 height of 11 or 12 mm. The posterior portion is more 

 abruptly constricted, the lamellose striations are not so 

 ])rominent and are more closely arranged. 



Fomnation and locnlUij. Clinton gnmp, McKee's ore . 

 bank, north-east of McKee's house, Ferguson valley, seven miles norlh-west of Lew- 

 istown, MitUin county, Pennsylvania. 



