Ijj PALEONTOLOGY OF NEW YORK. 



without specific name. From the Hudson river, Trenton and lower formations, 

 nine species of Bucania have been described. At the same time about twenty 

 species of Bellerophon proper have been described from all the formations 

 below the Devonian. 



The geographical distribution of the species herein described, appears, with 

 few exceptions, to have been quite limited. Bellerophon Pelops occurs in Ohio as 

 well as in New York. B. patulus B. Leda and B. Lyra have been found at the 

 Falls of the Ohio in the same horizon which they occupy in the State of New 

 York. B. patulus has also been found in the same horizon in Maryland and 

 Virginia, in the arenaceous, calcareous and mud shales, and in the limestone 

 of the formation, and probably occurs in the Hamilton group of Pennsylvania, 

 having the widest distribution of any of the species, and being far more 

 numerous in individuals than any other form. 



Since the preceding pages were printed, I have received from Dr. John S. 

 Newberry the originals of the species Bellerophon propinquus and B. Newberryi, for 

 the purpose of comparison with the specimens in my possession. Among 

 these are six individuals and several fragments of the latter species in various 

 conditions of preservation. In the two larger individuals, one presents no 

 evidence of dorsal band farther than in the one figured on plate 22, while 

 in the other a faint indication of such character may be detected. Several of 

 the smaller individuals show a distinct band on the posterior part of the outer 

 volution, which, in some at least, becomes obsolete on the anterior expansion. 



The transverse costae become gradually obsolete on the sides of the shell, 

 and merge into the ordinary striae of growth before reaching the umbilicus. 

 The same is also true of the anterior portion of the shell, which appears to be 

 marked only by striae of growth. In well-preserved specimens the transverse 

 costae are all cancellated by distinct, rounded, revolving striae, which also 

 become obsolete on the anterior portion of the last volution. When the last 

 volution is fully preserved, the peristome is very abruptly expanded ; the 

 columellar lip is always more or less covered by a callus, either as represented 

 in figure 16 of plate 22, or extending forward at the sides, as shown in B. 



