Journal of conchology . ril, 1901. lO JOURNAL OF CONCHOLOGY, VOL. II, NO. I, JANUARY, I9O4. that they might prove to be the ova of P. taylori, adult specimens ofthat species were collected and placed in glass vessels with ordinarytap water. In a very short time the little snails commenced to depositsimilar capsules on the sides of the vessels, thus proving their identitywith those previously observed on the reeds. These egg-capsules, which are deposited singly, are very similar tothose of the North American Amnicola porata, described by Dr. , in his Researches upon the Hydrobiinge a
Journal of conchology . ril, 1901. lO JOURNAL OF CONCHOLOGY, VOL. II, NO. I, JANUARY, I9O4. that they might prove to be the ova of P. taylori, adult specimens ofthat species were collected and placed in glass vessels with ordinarytap water. In a very short time the little snails commenced to depositsimilar capsules on the sides of the vessels, thus proving their identitywith those previously observed on the reeds. These egg-capsules, which are deposited singly, are very similar tothose of the North American Amnicola porata, described by Dr. , in his Researches upon the Hydrobiinge and allied forms.^They are somewhat lenticular in shape, horny, transparent, and areattached to objects by a flat base. The free portion is furnished alongits length with a broad thin laminated keel. The contained egg re-sembles very much a small fig seed, both in size and colour, and floatsfreely in the surrounding fluid. The capsules are deposited duringthe months of May, June, and July, and develop in about six Paludestrina , 2, Views of the shell; the line between them shows the natural size ;3, section of leaf and egg-capsule attached to it ; 4, view of leaf, with emptyegg-capsule attached; 5, leaf with capsule containing a partly-developedembryo ; figs. 3-5 magnified. During the two succeeding summers we have had the species underclose observation, with the same results; the egg-capsules were de-posited, and in a few days a change could be seen in the shape of thecontained egg. The first noticeable alteration occurred about tendays after deposition, when a rotatory motion was observable in theova, and they began to lose their spherical shape. About the middleof the fifth week they had developed considerably, and at this periodthe protoconch, consisting of about one-and-a-half whorls, was to beseen distinctly through the envelope of the capsule. These shellswere of a semi-transparent horn colour, and the animals could be seengently moving about. From this t
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Keywords: ., bookauthorconcholo, bookcentury1800, bookdecade1870, bookyear1879
