Gkabau — Faunas of the Hamilton Group. 



257 



Genus Palaeoneilo, Hall. 



54. Palaeoneilo constricta, Conrad 



1885, Hall, Pal. N. Y., vol. 5, pt. 1, p. 833, pis. 48, 51. 



This species occurs in the Lower shales, where I have found it at a depth 

 of twenty and forty -five feet below the Encrinal limestone. It is a rare form, 

 only four specimens having been found in all. I have not found it above 

 the S. demissa bed. The following are the measurements of three of the 

 specimens: length, 15, 14, and 14 mm. respectively ; height, 7, 9, and 10 mm. 

 respectively, showing thus some variation in the proportion of length to 

 height. 



55. Pal.eoneilo tenuistriata, Hall. 



1885, Hall, Pal. N. Y., vol. 5, pt. 1, p. 336, pi. 49, 93. 



This species is common in the lower portion of the Moscow shales, where 

 specimens in a good state of preservation may be obtained. It is most abun- 

 dant in the layers between two and three feet above the Encrinal limestone, 

 a single specimen only having been found in the lowest two feet. The species 

 has not been found above the lower three feet of Moscow shale, but below the 

 Encrinal limestone it occurs sparingly down to the base of the Hamilton 

 shales. A few doubtful specimens were obtained from the Strophalosia bed. 

 The specimens from the Lower shales are never so well preserved as are those 

 from the Moscow shales, while at the same time the depression of the umbonal 

 ridge is more marked, and the specimens rather larger than the usual size. 

 The depression of the umbonal ridge is but slightly marked in the specimens 

 from the Moscow shales, the posterior margin occasionally appearing regularly 

 rounded. In some specimens the surface stripe become so coarse that it is 

 difficult to distinguish them from the next species. 



56. Palaeoneilo eecunda, Hall. 



1885, Hall, Pal. N. Y., vol. 5, pt. 1, p. 336, pi. 49. 



This species was found associated with the preceding in almost all the 

 strata. It is less abundant than P. tenuistriata in the Moscow shales, but more 

 common and better preserved than that species in the Lower shales. I have 

 not found it lower than twenty-one feet below the Encrinal limestone. A 

 small specimen measures : length 13 mm. height 8 mm. 



