GASTEROPODA. 87 
recent shell, which Mr. Jeffreys considers as Zruncatella atomus, ‘Phil. En. Moll. Sic.,’ 
vol. ii, p. 134, Tab. XXIV, fig. 5. There is a figure of the animal and shell by Mr. 
Jeffreys in the ‘Ann. and Mag. Nat. Hist.,? January, 1859, p. 18, Pl. HI, fig. 16, 
where it is described under the name of Ewomphalus nitidissimus. 
Cacum tracuna, Mont. Crag Moll., vol. i, p. 115, Tab. XX, fig. 5. 
— mammituatum, 8. Wood. Crag Moll., vol. i, p. 116, Tab. XX, fig. 4. 
— tasrum, Mont. Crag Moll., vol. i, p. 117, Tab. XX, fig. 6 
— incurvatum, Walker. Crag Moll., vol. i, p. 117, Tab. XX, fig. 7, a, 6. 
The above four species were given by me in the ‘Crag Mollusca,’ but ¢acwrvatwm only 
provisionally, as being possibly the young of one of the other species. 
Dr. Philip Carpenter in his ‘Monograph on the Cacide” ‘Proc. Zoo. Soe.’, 1898, 
dissents from my determination of C. trachea, and regards the shell figured by me under that 
name as a new form, to which he assigns the name of ¢wmidum, rejecting the living species 
trachea from the Crag category! My species C. mammillatum he recognises, as well as 
C. glabrum, Mont., while C. incurvatum he also thinks may be the young of one of the other 
species. He also recognises among my specimens placed in the British Museum a new 
form, which he names /irafum ; and he makes new genera for the reception of all. 
As Dr. Carpenter has made the family of Cecid@ a special object of study, I think 
it desirable (though I do not fully agree with him) to give the Crag Cwcide according 
to his views, which are thus: 
Carprenter’s Names. Names IN Crac Mo.uusca. 
Elephantulum liratum . . . . . Not given. 
Anellum tumidum . . . . . . Cccum trachea, vol.i, p. 115, Tab. XX, fig. 5. 
Fartulum mammillatun . . . . ©. mammillatum, vol. i, p. 116, Tab. XX, ‘ A. 
Brochina glabra. . . . . ~. €. glabrum, vol.i, p. 117, Tab. XX, fig. 6 
Young of mammillatun . . . . C. incurvatum, vol.i, p. 117, Tab. XX, fig W 
Dr. P. Carpenter does not recognise any of these forms as living, with the exception 
of glabra. Mr. Bell gives (‘ Ann. and Mag., May, 1871) C. mammillatum from the Red 
Crag of Walton Naze. 
1 In my Catalogue in ‘ Mag. of Nat. Hist.,’ 1842, I placee a note of interrogation against C. trachea, 
and pointed out that the recent shell is regularly annulated and smooth, and that my Crag shell differed 
from it in haying the annuli more irregular and rugose. 
