280 PROCEEDINGS OF THE ACADEMY OF [Feb., 



sissippiensis and not so strongly alternating in size. Length of a 

 specimen of six body whorls 14 mm., width 4 mm. P. mississippiensis 

 seldom has more than five body whorls, and an average specimen 

 measures 13.5 mm. by 5 mm. 



Phos falsus n. sp. 



I have before me a remarkable Red Bluff Phos, which may be named 

 falsus. It is very much larger than macilentus, though nearly as slender. 

 The nucleus is as in that species and mississippiensis, consisting of 

 four whorls, the lowest of which is sculptured with very fine obliquely 

 sigmoid riblets. The body whorls are six in number, with rather 

 widely spaced longitudinal ribs, some eight in number, subequal 

 among themselves on the first four whorls, but then becoming very 

 widely spaced and finally completely disappearing, leaving the surface 

 even; the revolving lines are distinct but not very coarse, and are 

 mutually separated on the larger whorls by two or three fine, closely 

 spaced threads. The type before me has a strong rounded varix on 

 the sixth whorl and another forming the outer lip. Length 19 mm., 

 width 6 mm. 



Metula fastidiosa n. sp. 



In the Red Bluff bed there is an apparently undescribed Metula 

 greatly resembling gracilis Johnson, from the Lower Claiborne of Texas 

 {Proc. Acad. Nat. Sci. Phila., 1899, p. 75, PI. II, fig. 3). This species, 

 which may be named as above, has a smaller and more rapidly 

 pointed spire than gracilis, and has a greater number of varices. The 

 nucleus is simple, smooth, rather higher than wide, ogivally pointed 

 and of about three whorls, the subsequent whorls five in number, 

 broadly, evenly rounded at the sides in profile, each with a feebly ele- 

 vated fiattened varix, relatively rather wide, on which the longitudinal 

 ribbing becomes obsolete and the revolving lyrse also obsolete except 

 on the body whorl, where they continue uninterruptedly over the 

 varix, which here becomes relatively still wider though so slightly 

 elevated as to be scarcely definable. The ribs are small, and, from varix 

 to varix on the spire whorls, about 32 in number; on these whorls 

 the revolving grooves are about 10 in number, and, with the exception 

 of the two posterior and one finer anterior, do not cross the ribs but 

 appear as short excavated lines between them; on the body whorl, 

 however, all the grooves cross the ribs but are reduced in width on 

 their summits ; the ribs on the body whorl are also somewhat changed 

 in character, being notably less steep in cross-section on the side lying 

 in the direction of the growth of the shell. The columella is thickened 



