478 PROCEEDINGS OF THE ACADEMY OF [1896. 



Panopsea porrectoides var. AM. PI. XXII, fig. 4. 



By comparing our figure with Aldrich's, it will be seen that typi- 

 cal _/9o/TecioiV/e.'>' is much larger, more developed anteriorly, and with 

 urabones nearer the center of the shell. Yet they both belong to the 

 same section of the genus, and it is almost certain that the one is 

 the ancestor of the other. 



Locality, Gregg's Landing, Ala. 



Lucina greggi n. sp. PI. XXII, figs. 6 and 6. 



Specific characterization. — Size and general form as indicated by 

 the figure; marked exteriorly with concentric lines not deeply in- 

 cised ; interior with two diverging cardinal teeth and an anterior 

 lateral ; anterior muscular scar very large and extending from the 

 anterior lateral tooth to the basal margin of the shell; posterior 

 muscular scar comparatively small, rotund ; interior naturally (or 

 by disease) much thickened or calloused, a shallow channel extend- 

 ing from a little above the upper margin of the posterior muscular 

 scar obliquely to near the base of the anterior scar. 



A small specimen, magnified in fig. 5, and probably of this spe- 

 cies, shows an extremely deeply excavated ligament pit, reminding 

 one of Lucina elaytonia. In the old type specimen this pit broadens 

 out and the ligament seems to be attached very much as in Dodnia. 



Locality, Gregg's Landing, Ala. 



Pleurotoma nasuta Whitf. Plate XXII, fig. 7. 



This species is extremely variable in ornamentation. Sometimes 

 the spiral lines are few and coarse; at other times they are many 

 and fine. Our figure shows a specimen of the latter type. 



Locality, Gregg's Landing, Ala. 



Fusus rugatus Aid. PI. XXII, fig. S. 



The specimen figured is more perfect than the type ; it shows well 

 the characters of the anterior canal, especially its ornamentation. 



Locality, Gregg's Landing, Ala. 



Pseudoliva vetusta. PI. XXII, fig. 9. 



P. vehista Con. Foss. Sh. Tert. Form., 1833, p. 44. 



The large size to which certain species described originally from 

 Claiborne often attain in the Bell's Landing Lignitic has already 

 been the subject of various observations. Perhaps no species shows 

 to better advantage this tendency than does the present. Note the 

 great sutural callosity in connection with like developments on 

 Volatilithes petrosus and Rostellaria trinodifera. 



