STAiN'DIiN : CAl.CAKKOUS ECC.S OF TERRESTRIAL MOLI.USCA. 1 57 



sub-globular in sliape, measuring i"5 x i mm.; they are usually 

 deposited singly, but sometimes in little clusters of four to six. 



The eggs of Testacella haliotidea Drap. are 6 x 4-4 mm., with 

 opaque yellowish-white calcareous shells, oblong-oval in shape, eventu- 

 ally becoming somewhat pointed at both ends. In T. tnaugei Fer. 

 the eggs are acuminate-oval in shape, white, but gradually become 

 yellowish. The eggs of Testacella are peculiar in that, although 

 enclosed in a hard calcareous shell, when removed from the ground 

 and placed upon the hand, or in a warm place, they explode with a 

 })erceptible noise ; but they may be preserved if plunged at once into 

 boiling water. This is an equally good method of destroying the 

 vitality in other species of eggs too small to empty by "blowing." 



The eggs of Patyphanta busbyi Gray, from New^ Zealand, are white, 

 regularly oval, surface granular, and measure 13 x u mm. Suter 

 states that they are generally laid at the foot of large trees, under- 

 neath dead leaves. In P. urmda Pfr. the egg is white, roundly- 

 ovate, very finely granular, 5*25 x 4*4 mm. P. hochstetteri Pfr. has a 

 roundly-oval egg, finely granular, colour fulvous ; dimensions 10 x 8"5 

 mm. Schizoglossa novoseelandica Pfr. has white hard-shelled eggs, 

 coarsely granular, 4x3 mm. They are usually deposited under a 

 good thickness of decaying fern leaves in little heaps of from six to 

 fourteen. 



In such of the ovoviviparous species as have calcareous eggs, they 

 are arranged in succession in the upper part of the oviduct down 

 which they descend as developed. The egg-shell becomes dissolved 

 or is consumed by the embryo, which uses up the limy material in 

 building its own shell. The latter attains a considerable size before 

 extrusion from the parent. 



According to Pilsbry, some of the species of Tliysaiiophora^ Sagda, 

 and Zaphyseina have been found with hard-shelled eggs in the oviduct. 

 In Sagda hahicmaniana Ad. they are short oval, white and smooth. Of 

 the eggs of Okacina I can find no mention, except Tryon's remark 

 that the genus is oviparous, has elliptical, white eggs, with calcareous, 

 roughened shells. 1 have eggs of Glandina fnsiformis Pfr., from 

 ■Mexico; they are white, elliptical, and measure 8"5 x 5-25 mm. 

 Varicella glabra Pfr., from San Juan, has white, elliptical, calcareous 

 eggs, with slightly pointed ends, the shell covered with a raised 

 pattern of interrupted lines. 



Pyraviidula rotundata (Miill.) has white, opaque, ellipsoidal eggs, 

 not quite a millimetre in their longest diameter. They seem to be 

 deposited from early spring to late autumn in little clusters of eight 

 to fifteen, and may often be met with under rubbish, dead leaves, etc. 

 Helix aspersa IN lull, lays from forty to one hundred eggs, roundly- 



