140 
PROCEEDINGS OF THE PERTHSHIRE SOCIETY OF NATURAL SCIENCE. 
definite arrangement, being so curved as to form a ball. Sus- j 
pecting what it was, 1 made a slight opening in the mass, and 
found a hedgehog inside, which I covered up again and left. 
Though there were plenty of withered leaves lying about, the 
animal had rejected most of them, and taken the trouble to 
bring the grass from some yards distant. The grass may have 
been lying cut, but I am inclined to think that the hedgehog 
must have pulled it itself. From the position of the nest 
withered leaves of trees would have probably been blowm away, 
and left the creature exposed, while the long grass stems formed 
a much more compact and less easily destroyed nest. 
2. Seasonal Phenomena.—In former years X have brought 
before the notice of the Society, on several occasions, certain 
seasonal phenomena, such as the dates of the flowering of plants. 
These have some interest, as showing either the character of 
the season, or the precocity of certain plmts. From the absence 
of any long-continued and severe frost this winter, many more 
plants are in flower in the open air than would have otherwise 
been, and I have brought a few to lay before you. Home of 
them have just come into flower, but many have not been 
out of flower since autumn. The following is a list of those I 
have seen in my garden to-day, most of which I now show you: 
—1. Daisy (The daisy has been adopted by the Society as its 
badge, but I do not think that the reasons why this plant has 
been selected have ever been stated. In the first place, the 
daisy is'.an illustration of the fact that “Union is Strength,” for, 
being of the order Composite, its flowers are collected into a 
head, the different parts of which have different functions, but 
all tending to the common welfare; in the second place, the 
daisy is everywhere, and so the Society should be; in the third 
place, it is always growing and always flowering—that is, accom¬ 
plishing its work and never idle—and this is what the Society 
shouldXalso be ; lastly, though it is but a humble plant, and 
one of jthose common things which are too often despised because 
they are “common,” yet it shows, by its structure and colours, 
the wonderful beauty—whether of colour, of form, or of adapta¬ 
tion—that pervades all Nature.) 2. Snowdrop (just coming into 
fl over); 3.,.Buttercup (Ranunculus repens)-, i. Christmas Rose 
(Uelleborus niger); 5. Pansy; G. Stocks, of various kinds; 7. 
Roses; 8. Potentilla Fragariastrum; 9. Potentilla alba; 10. 
Cliickweed; 11. Groundsel; 12. Euphorbia Peplus; 13. Moon 
D Isy (Chrysanthemum leucantliemum); 14. Honeysuckle; 15. 
P ly-anthus {several kiuds); 16. Erodium Manescavi; 17. Veronica 
rupestris ; 18. Veronica spicata ; 19. Kerria japonica; 20. 
Pr ickly Oomfrey (Symphytum asperriinum); 21. Lamium macu- 
latum (two. varieties); 22. Poly gala Chamcebuxus; 23. Sweet 
Violet:' 2i.'^Erysimurn pulchcllum-, 25. Androsace camea; 26. 
Potentilla argentea; 27. Arabis procui-rens; 28. Poa annua; 29. 
Aubretia purpurea. 
The following paper was read: — 
“ The Life History of a Garden Snail.” By Mr H. 
Coates, F.R.P.S. 
In a former paper, giving notes on the Land and Fresh-Water 
Shells of Perthshire, I pointed out that these represent two well- 
defined classes of the sub-kingdom Mollusca,—the one having, 
amongst other distinctions, a shell consisting of two pieces or 
valves; and the other, either a shell consisting of a single valve 
or no distinct shell at all. The characters of the former, the 
Lamellibranchiata, I have described in a paper on the pearl- 
mussel of the Tay (Unio margaritiferus), which was selected 
as a type of the class. With the other, or Gasteropoda, I 
intend to deal under the present heading. 
In the first place, it is necessary to remark that land and 
fresh-water snails do not by any means constitute the whole, or 
even the majority, of this important class, which comprises as 
welt what have sometimes been called “the snails and slugs of 
the sea.” Instead of describing in general terms the structure 
and habits of the Gasteropoda, let me select as a type what is 
known in England as the common garden snail (Helix aspersa), 
—a snail which, however, is fortunately not quite so common in 
Scotch gardens as in English. If we examine this species, and" 
trace its history, we shall perhaps have gained a clearer idea of 
the characters of the class than could have been conveyed by a 
a more general description. 
I will ask you to accompany me, in imagination, on a snail¬ 
hunting ramble, say towards the end of August, and try what 
we can observe of the life-history of these creatures. Leaving 
the dusty highway, we will search out some unfrequented spot, 
such as the waste corners of fields, where weeds luxuriate ; or, 
better still, a rocky and shaded glen. Lifting carefully a patch 
of the damp moss, we may find, a little way under the surface of 
the loose soil, a group of small round bodies of a creamy white. 
These are the eggs of the snail, laid carefully where they will be 
moist, and undisturbed. They measure from the tenth to the eighth 
of an inch in diameter, and may number as many as 100, or 110. 
Sometimes they are glued together in clusters, sometimes 
separate. The eggs cf some of the African cousins of our s nail 
are magnificent objects compared to these little white balls, 
being ha!f-an-inch long, and enclosed in a hardened shell. If we 
replace the moss, and visit the spot again fifteen or twenty days 
later, we shall find, in place of the eggs, a group of tiny 
mollusks, each possessing, though newly hatched, a transparent 
spiral shell, complete in form, but so fragile that the slightest 
pressure will crush it. The young snails spend their early days 
c .iefly in their place of concealment, only coming out for a little 
while on damp evenings, and during this time they grow very 
rapidly. The shell increases in size by continual additions to the 
elge of the lip, and in thickness by the addition of layers to the 
inuer surface. 
By the end of October, those members of the brood which 
have not fallen a prey to the attacks of birds and other enemies, 
will have attained the size of hazel nuts. If we take up one to 
examine it, however, we must remember that the strengthening 
of the shell has not kept pace with its growth, and that the 
least rough handling will break it. The mouths of young shells 
are particularly delicate, for it is not until they are full-grown 
that the strong rib is added which gives to this part the strength 
which, in the rest of the shell, is supplied by its spherical form. 
On the approach of frost, the snail—which is sensitive to both 
extremes of temperature—prepares for its winter seclusion. It 
