A PRACTICAL METHOD OF SPONGE CULTURE. ; 555 
GROWING FROM DEGENERATIVE BODIES AND TEASED OR DISSOCIATED TISSUES. 
Wilson’s extremely interesting and scientifically important studies in this 
field open, as he points out, a new means by which sponges may be propagated. 
The experiments so far have been confined to noncommercial species, but there 
appears to be no reason for believing that they can not be applied to horny 
sponges. In fact, in certain “‘sick’’ sheepswool sponges in my experimental 
plants I have observed in the dead skeletal remains certain degenerative masses 
resembling, at least superficially, those described by Wilson in silicious sponges. 
Wilson’s methods are to induce the partial death of the sponge and the 
production of small degenerate bodies in the remaining living tissue, or to tease 
up the soft tissue, or finely divide it by squeezing it through bolting cloth bags. 
The resulting small masses speedily attach and regenerate into little sponges. 
Leaving out of consideration the morphological significance of these 
processes, and viewing them solely from the practical standpoint of sponge cul- 
ture, these methods of rearing sponges appear to be essentially similar to rearing 
from cuttings made with a knife, the main difference being that the tissue aggre- 
gates, or pieces, are obtained by an elaborate method instead of a simple one. 
GROWING FROM CUTTINGS. 
‘This method was adopted as that giving greatest promise of success, and 
it is discussed in detail in the following chapters. 
PROPAGATION OF SPONGES FROM CUTTINGS. 
Growing sponges from cuttings has to recommend it, as a practical method, 
its simplicity and the certainty with which the excised pieces will attach and 
regenerate when placed under suitable conditions. The ease with which suitable 
seed sponges may be obtained at any season, their immunity from the effects of 
more or less rough handling, the facility and rapidity with which they can be 
attached to such materials as may be selected, the promptness with which they 
will grow fast to suitable foreign bodies, and the certainty with which they heal 
and grow into perfect sponges make this an immediately feasible method of 
sponge culture, provided the proper means of attachment and methods of han- 
dling can be developed. How far the present experiments have solved the prob- 
lems will be seen in the following account. 
SEED SPONGES. 
For seed any healthy sponge may be used, whatever its shape or size. Torn 
and irregular specimens, or those so filled with sand and other foreign matter as 
to make them of little value in the markets, may be utilized equally with well- 
shaped ones, though they often do not cut so economically in respect to either 
material or time. When the seed sponge is heavily loaded with shells, corals, 
