Mr. W. H. Benson on the genus Diplommatina. 193 
the tube. It is possible that in the specimen referred to, the 
flowers are only in a young state, and that when fully grown 
they may assume a somewhat greater development, but I give the 
description in accordance with the specimen as it exists*. 
XXII.—Characters of Diplommatina, a new genus of Terrestrial 
Mollusks belonging to the Family of Carychiadee, and of a second 
Species contained in it ; also of a new species of Carychium in- 
habiting the Western Himalaya. By W. H. Benson, Esq. 
At page 81, vol. ii. of Pfeiffer’s excellent Monograph of the 
Helicide, there appears an erroneous reference to that family of 
an anomalous shell, the animal of which must exclude it from 
the position there assigned to it ;—I allude to the little Himalayan 
species called by Capt. Hutton in MSS. Carychium costatum, 
which Dr. Pfeiffer has described under the title of Bulimus folli- 
culus. Capt. Hutton, referring to the situation of the eyes and 
to their not being borne on the summits of the tentacula, asso- 
ciated the form with Carychium. The shell alone, differmg in 
the shape of the aperture and destitute of plaits or teeth, would 
certainly be anomalous in that genus; but it formed the only 
published type to which the species could be approximated. The 
following is the recorded result of my own repeated observations 
of the animals of both species. 
Tentacula two only, originating from the upper part of the 
head, long and filiform ; eyes situated on the posterior part of 
the tentacula at their base, composed of two lobes: one lobe 
deeply seated in the tentaculum and larger than the other lobe, 
which is a small black point coming to the surface on the outer 
side of the larger lobe ; foot short. 
Had the animal been provided with an operculum, it might 
possibly have been referred to the family of Cyclostomatid in 
accordance with the position of the eyes, and the form of the 
aperture of the shell. The differences observable in the latter, 
as well as in its inhabitant, give countenance to a separation from 
Carychium ; I therefore propose for the type the followimg name 
derived from the peculiarity of the percipient points or eyes. 
Diplommatina, nobis. 
Char. Gen. Testa vix rimata, tenui, subovata; spira elongata; an- 
fractibus convexis, costatis, ultimo subascendente ; apertura eden- 
* A representation of this plant with details will be shown in plate 48 of 
the ‘Illustr. South Amer. Plants.’ 
+ I believe I have the concurrence of the major part of the conchologists 
of the present day in dissenting from Rang’s opinion, ‘qu’il n'est pas possible 
d’établir des divisions fondées sur la présence ou |’absence d’opercule, ’— 
Vide Rang’s Manuel, p. 198, Art. Litiopa. 
Ann. & Mag. N. Hist. Ser. 2. Vol. iv. 13 
