40 PALEONTOLOGY OF NEW YORK. 



LoXi'M.M \ ? SUBATTENUATA. 



ri.\i i. \iii. ni.s. 1-6. 



JLoxonemat tubalUnuata, Hall. Descriptions of New Species of Fossils, etc., p. 24. 1861. 

 » •• Fifteenth Rep. N. Y. State Cab. Nat. Hist., p. 52. 1862. 



" " " Illustrations of Devonian Fossils: Gasteropoda, pi. 13. 1876. 



Shell turretiform, elongate; spire somewhat rapidly ascending. Volutions six 

 or more, moderately convex, gradually expanding from the apex, the last 

 one somewhat ventricose towards the aperture. 



Surface unknown. 



A cast of a species having proportions nearly similar to Murchisonia Maia 

 occurs in the Schoharie grit ; but the shell has tapered somewhat more rapidly, 

 the volutions are more ascending and less convex, and the form of the aperture 

 is subovate and narrowed below. In one specimen the length from base of 

 aperture to top of the sixth volution is one inch and three-fourths, and the 

 diameter of the last volution is about five-eighths of an inch. A larger indi- 

 vidual, referred to the same species, has a length of two and a quarter inches. 



In this species the volutions are less rapidly ascending, and the spire less 

 attenuate than in L. attenuata of the Lower Helderberg group, which in many 

 respects it resembles. 



Formation and locality. In the Schoharie grit at Schoharie, N. Y. 



LoXONEMA ROBUSTA. 



PLATE XIII, FIGS. 4, 6, 6. 



Loxonema robusta. Hall. Descriptions of New Species of Fossils, etc., p. 24. 1861. 

 Fifteenth Rep. N. Y. State Cab. Nat. Hist., p. 52. 1862. 

 " " " Illustrations of Devonian Fossils: Gasteropoda, pi. 13. 1876. 



Shell robust, terebriform ; spire rapidly ascending. Volutions moderately con- 

 vex, the last slightly more ventricose, with a diameter of nearly an inch. 

 The length from the base of the aperture to the summit of the fourth volu- 

 tion, in a specimen which has been compressed, is three inches, and in a more 

 rotuii'l specimen the same number of volutions measure a little less than three 

 inches ; above this there have probably been three or four volutions to the 

 mi in in i t , adding to the length about three-fourths of an inch. 



