SPONGIDA. 73 
same time, however, the trade in this product goes on yearly increasing, 
But it is only a question of time when the trade shall cease; the 
demand which every year clears the submarine fields of these sponges 
causing such destruction that their reproduction will soon cease to be 
adequate. 
In order to prevent such a result, it is very desirable that 
attempts should at once be made to naturalise the several species of 
sponges on the French and Algerian coasts, and that their cultivation 
and reproduction should be protected. For this purpose the rocky 
coasts of the Mediterranean, from Cape Cruz to Nice, at Hyeres, 
and even some of the salt lakes of the departments in Algeria near 
the Mediterranean, might be utilised ; large portions of the Southern 
Italian littoral zone would also be available for this purpose. 
M. Lamiral considered that the composition of the water of the 
Mediterranean being nearly the same on the coasts of France, of 
Algeria, and of Syria, the difference of temperature between these 
two places—especially at the depth where the sponges flourish most 
—would not interfere with their existence, and he believed that 
their acclimatisation on the coasts of France and Algeria would be a 
certain success. He remarked, moreover, that the more the sponges 
advanced towards the north the finer and compacter their tissues 
became ; and he argued from this fact that a considerable improve- 
ment in their quality would result from the experiment. 
The only difficulty, then, would be in the transplanting sponges 
from the Syrian waters to the coasts of France and Algeria. A sub- 
marine boat, such as M. Lamiral makes use of for scientific operations 
conducted in deep water, would, according to this naturalist, give 
every facility for collecting sponges for the purpose. This boat can 
‘descend to great depths, and its crew can even dwell there for a 
considerable time, for it is continually fed with fresh air, which is 
conveyed by an air-pump and tube into the interior of the boat from 
above, so that the men could readily select such specimens as were 
suited for acclimatising ; removing whole blocks of rock along with 
them, either by placing them in cases pierced with holes, or by 
towing them to their new abode. 
It might be possible, too, to collect the very young forms of sponge 
in the months of April and May, shortly after they have commenced 
their independent existence, and to transplant them to favourable 
localities. At the end of three years, when these true submarine 
fields would be probably ripe for harvesting, they could be farmed 
out for methodical collection, which would be effected by means of 
diving boats. 
