4 PEOCEEDINGS OF THE NATIONAL MUSEUM vol. 82 



whorl with still lighter streaks on a grayish-white ground, earlier 

 whorls uniform whitish. The first whorl is smooth, the rest with very- 

 fine, irregular, oblique striae decussated by closely engraved spiral 

 lines ; these are somewhat weaker on the last whorl, which is distinctly 

 malleate on the back. The whorls are only moderately convex, the 

 last angular at the periphery in front, the angle disappearing on 

 the back. Suture shallow, narrowly marginate, and minutely, not 

 very strongly, crenulate. The ovate, oblique aperture shows the ex- 

 ternal color markings. Lip thin, white, the basal margin rather 

 deeply concave. Columella subvertical, faintly brownish, obliquely 

 truncate anteriorly. 



Length, 33 mm; diameter, 19.4 mm; aperture, 18 mm long; 5% 

 whorls. 



Remarks. — ^Doctor Lea's first description of this species was from 

 the specimen illustrated in Plate 1, Figures 1, 2, and redescribed 

 above. He subsequently thought that this shell represented an im- 

 mature stage of a much larger form, which he had from the same 

 place and collector, and his second description ^ was from this larger 

 form, which differs from the original type in size, shape, color, and 

 number of whorls. Copies of Lea's two descriptions have been given 

 in Manual of Conchology, vol. 16, p. 253, 1904. His opinion that the 

 two shells were young and adult stages of one species was certainly 

 erroneous. They are both adult and belong to appreciably different 

 groups of species. I am describing Lea's second conception of A. 

 turhinata as Pseudotrochus leai. 



Lea did not figure his species, and his comparison with ^^Achatina'^ 

 itammata led later authors to refer it to the genus Liviicolaria. 



Keeve's Bulvmus turbinatus, which he doubtfully identified with 

 Lea's species, is an entirely different West African L'unicolaria. 



P. twhinatus is very closely related to P. mucidus (Gould), de- 

 scribed some years later, but turhinatus differs by its sparser mark- 

 ings and the subangular last whorl. Further collections are needed 

 to determine whether there is intergradation ; the small series in the 

 collections of the Academy of Natural Sciences of Philadelphia and 

 the National Museum do not show any intermediate stages. 



PSEUDOTROCHUS LEAI, new species 



Plate 1, Figures 6, 7 



Achatina turbinata Lea, Trans. Amer. Philos. Soc, vol. 9, p. 2, Apr. 5, 1844; 

 repeated in Observations on the genus Unio, vol. 4, p. 2, 1848. (Not A. 

 turbinata Lea, 1841.) 



Type.— U.S.N M. No. 406385, collected by Doctor Blanding m 

 Liberia and received with the Lea collection. 



' Trans. Amer. Philos. Soc, vol. 9. p. 2, 1S44. 



