PYRAMIDULA ROTUNDATA. 183 
Reproduction and Development.—No details are known of the 
congress of this common species, except that during conjugation the seminal 
matter is probably transferred in a fluid condition and not by means of a 
spermatophore or capreolus. 
The process of egg deposition probably commences as early as February, 
and is continued quite to the end of the year. The eggs to the number of 
twenty or thirty, are Jaid among or beneath Sect dead leaves, ete., and 
at the foot of trees, in little clusters, containing eight, ten, or even fifteen 
eggs each, and are small, white, opaque and ellipsoidal, nearly a millimetre 
in their longest diameter, the ratio of the two diameters being about the 
same as those of the tawny owl. ‘They hatch in ten or twelve days, the 
young and immature shells differing from the adults in being quite flat 
above and very convex beneath ; they become adult in about a year. 
Pyramidula rotundata is perhaps lable to produce alien offspring, as 
Mr. H. Beeston has observed it in coition with //yalinia alliaria ; while 
Dumont and Mortillet remark that at Sommier au Reposoir in "Savoy 
many individuals are found quite intermediate im character between the 
present species and P. ruderuta, which are probably true hybrids, as both 
species are found intermixed there. 
Habits, Food, etc.—Pyramidula rotundata is slow, apathetic, but 
somewhat sensitive, and is an ubiquitous species in many parts of the 
country, frequenting almost indiscriminately nearly every variety of 
situation. It is said to be the commonest of the smaller Helicidiform 
species on the greensand formation and is also abundant on the chalk. 
P. rotundata is crepuscular or nocturnal in habit, but may be. found 
during the day, secreted beneath stones, dead leaves, loose or decaying 
bark or timber laid on the ground, or even on dry mud banks or among 
stoneheaps by the roadsides. It may also be discovered on or at the foot 
of old stone walls, in old quarries, or woodstacks amongst turf or moss, 
at roots of nettles, or amongst ivy and decaying hedge- trimmings, by 
stream-sides, in dry or wet places indifferently, and even invading the 
precincts of buildings and damp outhouses, where it sometimes attains a 
large size ; indeed, it is scarcely possible to imagine a situation capable 
of sustaining molluscan life where it may not be found. 
Though so accommodating in its requirements, this species is said in 
France to prefer places with a northern or eastern aspect, but this is 
probably not the case in more sunless countries. 
It lives at almost all altitudes, from the lowland plains to the alpine 
heights, but, according to Prof. Forbes, not ascending in Switzerland 
beyond the zone of dwarf pines, while in the Pyrenees Dr. Fischer records 
it from the zone of the rhododendron at altitudes between 5,000 and 
6,500 feet. 
Among its enemies, blackbirds and starlings are well known as feeding 
readily upon it, many shells having been found in their crops. 
Little or nothing is known of the food preferred by this species ; it has 
been said to devour dead and decaying leaves and even decaying wood, 
while in wet places it frequents and perhaps feeds upon /yguisetum 
telmateia. 
In captivity, Dr. Gain offered at different times to colonies of this 
species 194 different kinds of food, but of this large number none were 
