MOLLUSCA. 755 



height of shell, 24 mm. ; maximum diameter, 25 mm. ; height 

 of aperture, 12 mm.; width of aperture, n mm. Volutions 

 about three and one-half or four in number, the spire depressed, 

 the suture ill-defined; the anterior portion of the shell rather 

 abruptly contracted from the body of the shell. Aperture sub- 

 circular, slightly higher than wide, with a very narrow anterior 

 canal ; the outer lip with a rather thick, slightly undulating mar- 

 gin, inner lip rather thick. Surface of the outer volution marked 

 by seven strong, revolving ribs separated by somewhat wider, 

 rounded furrows, with an eighth less conspicuous one upon 

 the anterior, canaliculate portion; the first three of these ribs, 

 next to the suture, occupy the upper surface of the volution, 

 the interval between the first and second being somewhat 

 greater than between the other ribs; the revolving ribs are 

 crossed by strong vertical folds at somewhat variable intervals, 

 but which are usually a little more distant than the revolving 

 ribs ; at the points where the vertical and revolving ribs cross, 

 the surface of the shell is elevated in conspicuous nodes; sur- 

 face also marked by fine, more or less irregular lines of growth. 



Remarks. The type of this species is a nearly perfect ex- 

 ample from the Ripley formation at Chatfield, Navarro County, 

 Texas, No. 21070 of the invertebrate paleontological collection 

 of the U. S. National Museum. In New Jersey a single imper- 

 fect individual has been observed. 



Formation and locality. Marshalltown clay-marl, near 

 Swedesboro (177). 



Geographic distribution. New Jersey, Texas. 



Family FTJSIDAE. 

 Genus Fusus Lamark. 



Fusus holmesianus Gabb. 

 Plate LXXXIX., Fig. 4. 



1860. Fusus Holmesianus Gabb, Jour. Acad. Nat. Sci. Phil., 



2d ser., vol. 4, p. 389, pi. 68, fig. 4. 

 1864. Fusus Holmesianus Meek, Check List, Inv. Foss. N. A., 



Cret. and Jur., p. 22. 



