PRACTICAL PROCESSES IN VEGETABLE HISTOLOGY. 49 
spores produced. Volvox is very plentiful. I have lately collected 
a few shells, being within easy distance from the seaside, or rather 
quite close to the harbour, for on the shore of the open sea it is 
not safe to venture on the rocks as there is such a tremendous 
swell. This is always on. Even when the sea is smooth the swell 
is simply frightful. You may get down on the rocks and think 
you are all right, when the sea comes rushing in two or three 
yards high, and you have to run at once, or be in danger of 
getting washed out into deep water. Many a time I have turned 
over a stone and seen a nice lot of shells, but before I could pick 
them up I have had to run, and of course the shells are washed 
away. ‘There are no boats on the coast on account of the surf and 
sharks, which are numerous. In fact bathing is only safe in places 
fenced off for the purpose. I got a fine lot of Sfzrw/a, a shell 
belonging to a cuttle fish, being the only living representative with 
an internal chambered shell and representing some of the fossil 
shells not very far from the belemnites. There is a place about 
ten miles from here where the Zchidna hystrix is found, but 
it would require ferrets to get them, or I should have made 
an attempt before now.” 
Pec ticAl PROCESSES IN VEGETABLE 
HISTOLOGY. 
By L. Oviver, in Rev. Sci. Nat, 1882 
(Continued from page 4.) 
IV. PRECIPITATION, CRYSTALLIZATION. 
HE substances whose precipitation or crystallization is produced 
in the interior of the cells are asparagin, inulin, and the sac- 
charoses. ‘Their deposition can be incited by a solution which 
contains principles different from those that are being sought for 
or even (according to the method originated by Borodin *) 
saturated with the substance itself which it is proposed to discover. 
Asparagin.—Asparagin crystallizes in this way in cells when 
treated with a saturated solution of asparagin. It is even the best 
means of showing its presence. It is obtained in greater quantity 
by immersing the tissues in absolute alcohol, which on subsequent 
evaporation leaves the asparagin in crystals. But as the alcohol 
also takes up other substances capable of crystallizing, in order to 
* Bot. Zig., 1878, p. 804. 
