132 Transactions.—Zoology. 
The radula (fig. 29) wants no explanation. The formula 
is 26—1—26, with five distinct lateral teeth. 
I am still of opinion that 0. dimidiata belongs to the genus 
Vitrinoidea, Semper, but I think it to be safer to retain the 
generic name proposed by Professor Hutton until I have been 
able to compare dentition and genital organs of our molluge 
with those of a Vitvinoidea from the Philippine Islands. Bus 
the animal perfectly agrees with Semper’s diagnosis of the 
genus; and there is one important fact which should be taken 
into consideration: O. dinudiata, when resting, brings its tail 
forwards beside the body and head, a position I have never 
seen taken up by any other mollusc. The figure of Vitrinoidea 
albajensis given by Semper (Philippinen, vol. iii., Taf. viii, 
fig. 2) shows a very similar position of the animal, and it seems 
that Semper has also been struck by its peculiarity. The 
figures of the teeth given by Semper are quite insufficient for 
comparison. 
NEw SPECIES AND VARIETIES. 
I. Lagochilus fasciatum, n. sp. Plate XIX., figs. 30, 31. 
Shell small, turbinate, subperforated, rufous, not shining, 
rather thin, with close membranaceous, white, slightly sinuated 
radiate plaits, about 11 or 12 per millimetre. They are crossed 
by numerous distinct spiral strie. Spire conical, apex rather 
blunt, smooth. Whorls 6, rounded, the first five slowly and 
regularly increasing, the last rapidly growing in size. Peri- 
phery rounded. There is a distinct horny band below the 
periphery on the last whorl, as is sometimes seen also in 
L. paludwm, Hutt. Suture impressed. The notch in the 
peristome is slight, but quite evident at the point where the 
upper margin meets the whorl. Aperture almost circular, 
diagonal ; peristome simple, straight, strengthened inside by 
a callous ring, the callosity extending over the body-whorl 
between the convergent margins. Umbilicus very narrow, 
previous, partly covered. Base rounded. 
Operculum not seen. 
Ammal unknown. 
Diameter, 2mm. ; height, 24mm. 
_ Hab. Near Manaia, Waimate Plains, North Island, where 
1t was collected by Mr. R. Murdoch, of Wanganui. | 
_ Note.—This species is near L. hedleyi, mihi, but may be 
distinguished from it by the more elevated spire, the less 
rounded whorls, the more numerous and equidistant plaits, 
the very distinct spiral striation, and the horny band on the 
last whorl. 
It is smaller than L. cytora, the spiral striee are much 
‘loser, and im the latter the radiate plaits are provided with a 
hair at the point where they cross. the spiral striae. - e 


