lO JOURNAL OF CONCHOLOGY, VOL. II, NO. I, JANUARY, I9O4. 



that they might prove to be the ova of P. taylori, adult specimens of 

 that species were collected and placed in glass vessels with ordinary 

 tap water. In a very short time the little snails commenced to deposit 

 similar capsules on the sides of the vessels, thus proving their identity 

 with those previously observed on the reeds. 



These egg-capsules, which are deposited singly, are very similar to 

 those of the North American Amnicola porata, described by Dr. Wm. 

 Stimpson, in his "Researches upon the Hydrobiinge and allied forms."^ 

 They are somewhat lenticular in shape, horny, transparent, and are 

 attached to objects by a flat base. The free portion is furnished along 

 its length with a broad thin laminated keel. The contained egg re- 

 sembles very much a small fig seed, both in size and colour, and floats 

 freely in the surrounding fluid. The capsules are deposited during 

 the months of May, June, and July, and develop in about six weeks. 



Paludestrina taylori. 

 I, 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 empty 

 egg-capsule attached ; 5, leaf with capsule containing a partly-developed 

 embryo ; figs. 3-5 magnified. 



During the two succeeding summers we have had the species under 

 close 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 the 

 contained egg. The first noticeable alteration occurred about ten 

 days after deposition, when a rotatory motion was observable in the 

 ova, and they began to lose their spherical shape. About the middle 

 of the fifth week they had developed considerably, and at this period 

 the protoconch, consisting of about one-and-a-half whorls, was to be 

 seen distinctly through the envelope of the capsule. These shells 

 were of a semi-transparent horn colour, and the animals could be seen 

 gently moving about. From this time they gradually increased in 

 size until they filled the whole of the capsule, which then burst, and 

 the young emerged. 



