= i 
Fuly 30, 1885] 
NATURE 
on 
at other times it usually takes refuge in an untenanted old shell 
of the common whelk (Buccinum undatum), where it is secure 
from the gobies and other fishes in the tank, and where it 
watches—as one can see its fellows do so at any time on the 
sea-coast in the middle of a rock-pool—expecting the return of 
the tide and prepared to adapt itself thereto. In ‘‘A Year at 
the Shore,” pp. 215-16, Mr. P. H. Gosse, F.R.S., mentions, 
on the authority of Mr. Ross, of Topsham, the case of a blenny 
which for five months proved ‘‘a regular and correct tide-indi- 
cator,” spending a portion of its time on the rock-work, and 
going back to the tank at the time of the return of the tide. 
I quite agree with Mr. Arthur R. Hunt’s idea that it would 
be a great gain if we could copy Nature a little closer, and have 
‘*working-models of the sea in some of our new aquariums,” 
Birmingham, July 22 W. R. HuGHEs 
Artificial Earthquakes 
Pror, MILNE’s experiments with artificial earthquakes in 
Japan, noticed in NATURE of June 4 (p. 114), show that the 
vertical free surface-wave had the quickest rate of transit, and 
this was taken to account for the preliminary tremors of an 
earthquake. The normal wave travelled with a less velocity, 
and the transverse wave slowest of all. In the earthquakes 
which occur here from time to time there are generally, if not 
always, two distinct shocks felt, and it is possible that the 
second is the transverse wave following on after the swifter 
normal vibration. I have not heard that there are any seismo- 
graphs in the Punjab, and in the alarm of the moment it is not 
easy to notice the direction of the motion without apparatus ; 
fortunately our earthquakes do not leave any automatic record 
in the shape of fissures or fallen buildings. But Prof. Milne’s 
experimental results are curiously confirmed by observations in 
Kashmir during the earthquakes of this month, which do not 
appear yet to have quite subsided. The Kashmir correspondent 
of the Lahore Ciwil and Military Gazette of to-day’s date writes 
as follows :—‘‘ The more severe shocks seemed to be followed 
by others in a different direction, like cross waves. I noticed 
this in a boat which quivered all over during a severe earth- 
quake, but rolled somewhat afterwards.” T. C. LEwIs 
Government College, Lahore, June 29 
The Recent Earthquake in Switzerland 
THE following is a table of events of the earthquake in 
Switzerland of June 20 last, compiled from numerous and inte- 
resting observations of the phenomenon, obligingly forwarded to 
me from all parts of the country. 
The earthquake consisted of a series of shocks :— 
1. Preparatory Shocks.—Very weak and ill-defined from mid- 
night to 3 a.m. ; at Neuchatel and Chaud-de-Fonds. 
2. Great Shock —At 5.16 on the morning of June 20; at the 
centre of the earthquake. 
3. Consecutive Shocks.—At 7.26 a.m. June 22 at Neuchatel ; 
at 8.30 a.m. of June 22 at Yverdun, Payerne, Estavayer, Con- 
cise, Boudry, Neuchatel ; at 11 a.m. of June 23 at St. Imier ; 
at 2.30 p.m. of June 23 at Neuchatel; at 9.20 a.m. of June 24 
at Yverdun (?) 
The great shock had its centre near Yvonand and the central 
area may be defined by the triangle formed by Yverdun, Neu- 
chatel and Payerne. The shock was strong enough to alarm 
the inhabitants, to displace some articles of furniture and even 
to throw down a chimney at Payerne. I assign to the shock 
the strength of number 6 on the scale of intensity, of which 
number Io would stand for the highest degree. The shock was 
felt more feebly in a vast territory extending as far at least as 
Geneva, Le Brassus, Le Locle, Bale, Glaris, Thun, Saxon: 
that is, it traversed the whole plain of Western Switzerland from 
the Jura Alps, A subterranean noise was heard yery distinctly 
in the whole central area and even a little beyond it. 
The shock had very markedly the character of successive 
oscillations, horizontal or vertical, their direction differing 
according to the locality. Such is, indeed, the usual type of 
earthquakes, as has been shown by the study of them with 
registering instruments, and it is interesting to notice that the 
various observations of the earthquake of June 20 all perfectly 
concur in ascribing to it this character. F, A. FoREL 
Morges 
THE PITCHER PLANT 
HE variety of the Pitcher Plant (Sarracenia variot- 
arts) found in North America is carnivorous, being 
a feeder on various animal substances. 
Mrs. Mary Treat, an American naturalist, made, a few 
years ago, several experiments upon the plants of this 
species to be found in Florida ; and to the labours of this 
lady the writer has been indebted, in some measure, in 
the preparation of this paper. 
The Sarracenia derives its name of “ Pitcher Plant” from 
the fact of its possessing the following curious character- 
istics. The median nerve is prolonged beyond the leaves 
in the manner of a tendril, and terminates in a species of 
cup or urn. This cup is ordinarily three or four inches in 
depth, and one to one and a half inches in width. The 
orifice of the cup is covered with a lid, which opens and 
shuts at certain periods. At sunrise the cup is found 
filled with sweet, limpid water, at which time the lid is 
down. In the course of the day the lid opens, when 
nearly half the water is evaporated ; but during the night 
this loss is made up, and the next morning the cup is 
again quite full, and the lid is shut. 
About the middle of March the plants put forth their 
leaves, which are from six to twelve inches long, hollow, 
and shaped something like a trumpet, whilst the aperture 
at the apex is formed almost precisely in the same manner 
as those of the plants previously described. A broad 
wing extends along one side of the leaf, from the base to 
the opening at the top ; this wing is bound, or edged with 
a purple cord, which extends likewise around the cup. 
This cord secretes a sweet fluid, and not only flying 
insects, but those also that crawl upon the ground, are 
attracted by it to the plants. Ants, especially, are very 
fond of this fluid, so that a line of aphides, extending 
from the base to the summit of a leaf, may frequently be 
observed slowly advancing towards the orifice of the cup, 
down which they disappear, never to return. Flying 
insects of every kind are equally drawn to the plant ; and 
directly they taste the fluid they act very curiously. 
After feeding upon the secretions for two or three minutes 
they become quite stupid, unsteady on their feet, and 
whilst trying to pass their legs over their wings to clear 
them, they fall down. : 
It is of no use to liberate any of the smaller insects, 
every fly, removed from the leaf upon which it had been 
feeding, returned immediately it was at liberty to do so, 
and walked down the fatal cup as though drawn to it by 
a species of irresistible fascination. 
It is not alone that flies and other small insects are 
overpowered by the fluid which exudes from the cord in 
question. Even large insects succumb to it, although of 
course not so quickly. Mrs. Treat says:—“A large 
cockroach was feeding on the secretion of a fresh leaf, 
which had caught but little or no prey. After feeding a 
short time the insect went down the tube so tight that I 
could not dislodge it, even when turning the leaf upside 
down and knocking it quite hard. It was late in the 
evening when I observed it enter; the next morning I 
cut the tube open; the cockroach was still alive, but it 
was covered with a secretion produced from the inner 
surface of the tube, and its legs fell off as I extricated it. 
From all appearance the terrible Sarracenia was eating 
its victim alive. And yet, perhaps, I should not say 
‘terrible,’ for the plant seems to supply its victims with a 
Lethe-like draught before devouring them.” 
If only a few insects alight upon a leaf no unpleasant 
smell is perceptible during, or after, the process of diges- 
tion ; but if a large number of them be caught, which is 
commonly the case, a most offensive odour emanates 
from the cup, although the putrid matter does not appear 
to injure in any manner the inner surface of the tube, 
food, even in this condition, being readily absorbed, and 
{ going to nourish the plant. In fact, it would seem tha 
