170 
ON CORONA PFEIFFERI, var. GRACILIS, n.van., FROM 
S8.E. COLOMBIA. 
By Enpear A. Suiru, F.Z.S., ete. 
Read \1th April, 1902. 
Tue shell about to be described was obtained at the Rio Caqueta, 
S.E. Colombia, and has recently been acquired by the British Museum. 
It appears to be a variety of Orthalicus Pfeifferi, 
Hidalgo, and is remarkable for its elongate and 
very slender! form, and the black colour of the 
aperture and of the external markings. The 
longitudinal reddish and slightly wavy lines 
which are characteristic of typical specimens 
are less conspicuous in the present variety. 
Its length is 67 mm. and diameter 23, whereas 
a normal example is 60 mm. long and 24 broad, 
the aperture in both being 26 mm. in length. 
Corona is considered by Pilsbry* to be a 
subgenus of Zzguus, and to include Helix 
regina, Ferussac, Achatina perversa, Swainson, 
Bulimus incisus, Hupé, and B. regalis, Hupé, 
which are probably all forms of one and the 
same species. In my opinion these so-called 
species are more nearly related to some of the 
species of Metorthalicus, e.g., DL. atramentarius, 
Pfeiffer, and Jf. Adansoni, Reeve, than to 
Liguus. 
I do not think Mr. Pilsbry had seen specimens 
Corona Pfeifferi, var. of Corona Pfeifferi, or he never would have 
gracilis, n.var. placed in the genus Oxystyla a shell which is 
scarcely separable from the four so-called species of Corona referred to. 
1 Hence the name gracilis which I propose for this new variety. 
* Man. Conch., ser. 11, vol. xii, p. 174. 
