1921] NATURAL SCIENCES OF PHILADELPHIA. 317 



Turns rara Gabb. Plate XVII. fig. I. 



Turns {Surcula) rara Gabb, Tr. Am. Philos. Soc, xv, 1873, p. 207. 



This is represented by one imperfect specimen. The whorls are 

 flat, sculptured with spiral raised lines, about fifteen between su- 

 tures on the penult whorl. There are crowded, sharp and irregular, 

 axial striae. The upper whorls have a slight median angle. The 

 slit-fasciole is not distinctly differentiated on the last two to two- 

 and-a-half whorls, but above that it is slightly prominent and weakly 

 nodose. 



Length (broken at both ends) 42.5, diam. 16 mm 



Type no. 2941 A. N. S. P. 



Surcula jacquensis (Sowerby) Plate XXII, flg. 21, 22. 



Pleurotoma jacquensis Sowerby. Q. J. Geol. Soc, vi, 1849, p. 51. 



Considered by Gabb to be a synonym of Drillia henekeni, but it is 

 a distinct species of Surcula. The last whorl has nine or ten large 

 axial ribs which are crossed on the whorls of the spire by six spiral 

 cords, the upper one sometimes accompanied by one or two threads. 

 On the last whorl these cords and threads number about twenty-five, 

 and in many specimens alternate in size, especially towards the 

 anterior end. There is a spiral raised line just below the suture, 

 and the anal fasciole has weak growth-fines or is smooth. 



Length 67.3, diam. 26 mm. 



Type no. 2939 A. N. S. P. 



Surcula longicaudata (Gabb) Plate XVII, flg. 2. 



Turris (Surcula) longicaudaia Gabb, Tr. Am. Philos. Soc, xv, 1873, p. 208. 



This species I'esembles Drillia consors somewhat in form and sculp- 

 ture, but has the generic characters of Surcula. The two apical 

 whorls are smooth, remaining whorls of the spire with large, rounded 

 slightly protractive ribs, which are crossed by six acute, spiral 

 threads, which are a little widened where they cross the ribs. Be- 

 low the suture, and extending to the angle of the anal fasciole, there 

 is a series of short, slightly retractive riblets. The last whorl is 

 evenly reticulated with axial and spiral ridges, tubercular at their 

 intersections. The interstices are minutely papillose. 



Length 26, diam. 7.3 mm.; whorls 10. 



Type no. 2938 A. N. S. P. 



Surcula humerosa (Gabb) Plate XVII, figs. 4. 5,. 



Turris (Sui'cula) humerosa Gabb, Tr. Am. Philos. Soc. xv. 1873, p. 208. 



A variable species represented by three specimens, fig. 4 represent- 

 ing the intermediate form. One extreme approaches very close 



