SPONGE CULTURE. 605 
The sponges should be gathered by experienced men by means of the drag 
net rather than the hook. As soon as they are taken they are rid of their 
impaired parts, then fastened by wooden pegs, and, kept in water, towed astern 
of a boat. They are cut by means of a very fine saw into fragments measuring 
26 millimeters longitudinally, and care is taken that each of the fragments 
retain as much as possible of the ectotome. It was observed in the experiments 
made at Lesina that if the sea remained calm for twenty-four hours fragments 
placed directly on the rocks adhered and were susceptible of further development. 
In practice it would be better to attach these fragments to suitable supports. 
Attempts of this character with wooden or metal pegs in cavities dug in flat 
stones or on the walls of wooden boxes did not give any favorable results. 
The greatest difficulty presented by metal pegs comes from their oxidation. 
Moreover, these first attempts were greatly interfered with because the supports 
became covered with sand and ooze. It may likewise be that the too intense 
action of light impeded the growth of the cuttings. 
The apparatus constructed by Buccich gave far better results. The frag- 
ments of sponges, 72 in number for each apparatus, were perforated with a 
trepanning instrument, then threaded on bamboo sticks between two parallel 
horizontal boards. The apparatus was weighted down with stones and could 
be raised for examination by means of a handle attached to the upper board. 
The fragments were thus disposed beyond all risk of being covered with ooze 
and without any impediment to the free circulation of water, while the upper 
board of the apparatus served as a screen against the rays of light. The silicate 
varnish of the bamboo also protected the sticks most effectually against the 
action of boring insects, but the latter entirely destroyed the boards in a num- 
ber of installations. 
The place chosen for these experiments was a bay in which a certain current 
was felt, but which was well sheltered against the waves, and where the alge at 
the bottom were highly colored. The operation may be considered as having 
succeeded when at the end of three to four weeks it is possible to ascertain that 
the cuttings have adhered to their supports. Beginning from this moment the 
growth is quite rapid; the cuttings reach a double or treble size during the first 
year; the growth is more marked during the first and fourth (?) years than 
during the second and third. This result can but surprise, and it seems to show 
that the observations were made on a limited number of cuttings for the whole, 
and that the influence of some untoward accidents has falsified the results. 
But however this may be, the cuttings had reached quite a considerable size at 
the end of five years, and the experimenters were able to conclude that a com- 
mercial size could be attained within seven years, showing the method to be a 
practical one. 
