Records of the Indian Museum (A Journal of Indian Zoology) November 1924

The measurement taken was the maximum height of the shell from the extreme apex to the furthest point on the margin of the peristome. [...] 6 : 21 that survive a period of adverse condition and so live to form a varix in the shell and in view of the possible tendency to equlisation of the sexes in the later years of life it is interesting to note that the proportion of males to females with a varix in the second year of life is only 21.4 : 78.6 whereas in the third year of life it has risen to 42.9 to 57.1 so that at the end of [...] I selected a number of examples and measured the distance from the extreme apex of the shell to the furthermost points on the various cocentric rings and the results are given in the accompanying figure 10. [...] In the first place the radula of the young of this mollusis much more like that of other species in the family than is that of the adult. [...] The characters of the frontal stripe the narrow dark band in the middle of the front are of doubtful use in separating the species ; the width varies considerably and if the fly has been pinned before it has hardened the whole front is apt to collapse and the stripe may appear very narrow ; in the female albina the frontal stripe is strikingly narrow and the eyes widely separated.