THEBA CANTIANA. 83 
broken in the act; the probability of this eversion of the elongated ccecum 
or vestigial dart-sac as an excitatory organ prior to conjugation is shown 
by the researches of Prof. Boycott, who has demonstrated that during con- 
gress this organ still continues wholly or partially invaginated. 
The eggs are deposited in clusters in damp spots from May to October ; 
they are sixty to ninety in number, about 14 mill. in diameter, of an 
opaline white, and globular in shape, enclosed in a shining and semitrans- 
parent envelope, speckled with very minute opaque points of mineral matter, 
which increase as the envelope dries ; the eggs within an hour or two gradu- 
ally becoming brittle and white. ‘They hatch in about a fortnight; those 
hatching in the spring and summer seem to hibernate when half to three- 
quarters grown; the hibernation though varying according to severity or 
mildness of the season, usually continues from late November to March ; 
at these times the shell is buried in the ground, with the mouth upwards, 
closed by an epiphragm and level with the surface ; after hibernation the 
immature individuals commence almost at once to enlarge their shells, and 
many may be seen as early as the end of April with five to six millimetres 
of new shell growth, and practically full grown except for their peristome, 
the later hatched individuals maturing later. Many hibernate through a 
second winter. ‘The young are quite hispid, the hairs being whitish and 
bent or incurved,as in Hygromia, but this investment gradually becomes lost. 
Food and Habits.—Theba cantiana in this country is found chiefly 
in hedges and banks, often abundantly on nettles and other plants in wet 
or damp places ; it is also frequently found on the sandhills near the sea- 
shore, apparently preferring the stunted grass and herbage of such places 
to the more rank and luxuriant vegetation of the richer soils, but it is also 
found in its dwarf form to exist at 6,000 ft. altitude at San Pellegrino, Italy. 
During the day it can be frequently seen attached to the twigs and 
leafage of the vegetation and fully exposed ; and when roughly handled 
has the habit, shared with //. strio/atu and a few other species, of ejecting 
one or more drops of a clear tasteless Huid, like water. 
It is a very active and sensitive species, and on moist days and after 
rains crawls energetically about, carrying its shell in an inclined position 
and secreting a clear slime, and travelling 75 millimetres or more per 
minute on a horizontal surface, or at the rate of a mile in about 14 days 
and 16 hours, a speed scarcely exceeded by even Helix aspersa. 
The circulation of the blood is also active, and, as is usual, is much 
more vigorous in the young than in the adult. In the month of July 
respiration occurred from two to six times per minute, while the average 
number of heart pulsations of half-grown animals was 56 per minute, 
though adults beat only 44 per minute at the same time and place. When 
extending themselves from the shells the contractions increased to 69 per 
minute in the immature shells and to 53 in the adults; and when placed 
on the warm hand the pulsations rose to 106, and in one case to 120, per 
minute in the young, and to 77 in mature shells. 
Mr. George Roberts has actually watched this species feeding upon the 
growing blades of grass, and Mr. Ashford has noted it similarly occupied 
on dead grass beneath bramble brushes. The Rev. Ashington Bullen has 
recorded that at Reigate the species preferred nettles and dock, but that 
at Dover it haunted bramble bushes in April and May; while Vernon 
Wollaston states that their carnivorous predilection was shown by the fact 
