ZOOLOGY AM) BOTANY, MICROSCOPY, ETC. 749 



the sea, tiiej would grow, and in time become perfect sponges. This 

 was put to the test by an experiment conducted in the Bay of Soco- 

 lizza, commenced in 1863 and concluded in 1872. Though success 

 was rendered impossible by the determined opposition of the local 

 populace, it did not prevent the accumulation of a mass of valuable 

 information. 



The most suitable season for commencing the propagation is the 

 winter. The growth of the sponge, and the healing of the cut 

 surfaces, proceed much more slowly in winter than in summer ; but a 

 high temperature is dangerous, by reason of the great tendency of the 

 sponge to undergo rapid putrefaction. 



As to locality, choice should be made of bays sheltered from 

 strong waves and currents, but not quite still ; the bottom should be 

 rocky, and clothed with living algaj ; and there should be a moderate 

 ebb and flow of the tide. In all cases, the neighbourhood of the 

 mouths of rivers and subterranean springs must be avoided. The 

 freshness and liveliness of colour of the marine algae are sure indi- 

 cations of a suitable spot. The worst enemy of sponge culture is mud. 



The sponges chosen for cutting must be gathered by experienced 

 hands with all possible gentleness. They are removed either by 

 tongs or by drag-nets. 



At a low temperature in the cold season of the year, it is possible, 

 with sponges freshly caught on the spot, to proceed, at once to make 

 cuttings from them ; whilst during warm weather, it is necessary to 

 wait and see whether any signs of putrefaction make their appearance. 

 This reveals itself by the dulness and softness of the aftected part. 



The dissection is rapidly performed, either with an ordinary knife, 

 or better, with a fine saw-Kke blade, which is much less liable to 

 injury by the foreign matters so abundantly found in sponge. The 

 sponge is laid upon a smooth wooden board, moistened with sea water. 

 The size of the cuttings is usually about 26 c. mil. (1 cubic inch). It 

 is well that each cutting should have the greatest possible area of 

 uninjured outer skin. The cuttings are placed dii'ectly in the spots 

 where they are intended to resume growth. 



A healthy piece of sponge firmly attaches itself to any surface 

 with which it comes into intimate contact in a short time. Cut 

 sponges grow together again. The attachment takes place most 

 rapidly when the pieces have but one cut surface, and this is laid 

 upon the support— wood, stone, &c. During perfect calm, for at 

 least twenty-four hours, it is possible, according to Buccich, to plant 

 the cuttings upon the stony sea-bottom itself, and they will hold. 

 He saw pieces that were merely cast into the sea on an ordinarily 

 suitable rocky bottom, during perfect calm, attach themselves and 

 grow. Thus enlightened as to the natural habits of the sponge, 

 Buccich prepared stone slabs, 53 mm. thick, as a foundation. These 

 he perforated with holes, and fastened the cutting to them by wooden 

 pegs driven into the holes ; but it became evident that the mud and 

 sand of the sea-bottom, perhaps also excess of light, were inimical to 

 further growth. Lattice frames, having the form of floating tables 

 above, and with the sponges attached beneath, were tried. Prof. 



Ser. 2. — Vol. I. 3 D 



