THE MEDITERRANEAN NATURALIST 
Tiie assumed 10 square miles is a guess only, 
but the figures give an idea of the magnitude of 
the operation. I am not acquainted with the 
documentary evidence as to importation, but it 
most be strong indeed to be accepted. 
I have observed that the Maltese have a strong 
tendency to adopt the most heroic and marvellous 
solution of any given problem.” 
Disappearance of Spondylus gaederopus, 
L. and other species from Maltese Waters. 
Reference was made in the last number of the 
Mediterranean Naturalist anent the sudden, disap- 
pearance of oysters from the harbour of Sydney 
where they were formerly numerous, which disap- 
pearance is due m that particular case to the inva- 
sion of a Glenodium. This brought to my mind a 
similar fact that took place in this part of the Medi- 
terranean with the Spondylus gaederopus L. This 
Spondylus up to 20 years ago was a very common 
species here, so much so that it formed an article of 
food in the markets and was known in the vernacu- 
lar by the name of Gaidri , and even 10 years ago I 
remember that I used to see if sold, though sparing- 
ly, in the streets. Dr. Caruana in Mamo ; s Catalo- 
gue, and Benoit and Galea in theirs, note it as being 
very common and quite rightly too. At present the 
only specimens obtained are poor and of stunted 
growth and even these are very rare and they bear 
but little resemblance to the fine and malgrive 
specimens that were formerly so plentiful and 
which now are never seen; if is only on the beaches 
that one can perhaps collect some bleached valves 
of them: if they continue disappearing at this rate 
they will in a very short period have to be accoun- 
ted as an extinct species for these islands. 
I may also add to the fast-disappearing Spon- 
dylus , the Solen nayina; the Solecurtur coractatus 
Gmel: known under the name of Stocci and 
which were common at Renella; and the Purpura 
hcemastoma L. which I see noted in the Cata- 
logues of Maltese shells as common species. At 
the present time this does not stand good with 
regard to any of them and in the course of my 
visits to the sea fruit market and in the dredgings 
both of my friend Be, Galizia and of my own 
we never came across specimens of either. 
165 
Whatever be the reason for this fact, it must 
explain the disappearance of these molluscs from 
every part of our shores because, the Solen ex- 
cepted, they were not ' species confined to a single 
locality, but were widely distributed, and we have 
not before us a slight change in their frequency 
but from a degree of very frequent occurence we 
now find them to be almost totally extinct. 
On the contrary Dosinia Exoleta L. seems to 
have been rather, an uncommon species in Mamo’s 
and Gulia’s time, while now this species is very 
abundant indeed, in the Great Harbour at least, 
where I have often, when dredging, obtained 
hundreds of specimens. 
The like may be noted of Ostrea lamellosa , 
Brocchi—Coccli which has taken in the markets 
the place of Spondylus and which I believe has of 
late greatly augmented in numbers. 
Apart from the causes which have led to these 
variations, there is nothing astonishing in these 
changes which are constantly going on more or 
less in the faunas and floras of all countries. I 
trust that this will not be without some interest 
to our naturalists. 
Alfred Card ana Gatto. 
Science Gossip. 
The lavas ofJEtna contain a considerable num- 
ber of minerals, but iron is only found in a 
state of decomposition. 
The mountain abounds in asphaltus, ’ Itumen. 
and lapis obsidianus. Yitrolic and sulphurous 
acid are often met with; and near spots burnt 
by the lava alluminous schists are sometimes 
found. The lavas enclose a variety of precious 
stones such as garnets, hyacinths, and among 
others that noble stone the chrysolite. An an- 
cient lava near Aci. Reale yields zeolites of extra- 
ordinary whiteness. 
Water spouts are of frequent occurrence in the 
Mediterranean at all seasons ot' the year but ex- 
pecially so about the time of the Autumnal 
Equinoxes. 
The opposing winds that then contest for su- 
premacy bring together dense masses of cloud's 
and it is when these meet that the “spouts are 
usually formed. In localities like the Straits of 
