166 PROCEEDINGS OF THE ACADEMY OF [1887. 



that the low temperature to which it had been subjected would 

 prove fatal to the germs, but, as the specimen was a fine one, it 

 seemed well to save it, even in its skeletonized condition. So, when 

 its icy envelope had been melted off, the sponge was again thorough- 

 ly washed until all the sarcode was removed, when, in a fresh jar, 

 it again became a parlor specimen. 



I do not clearly remember when signs of germination were first ob- 

 served. It was probably in January, as during that month I find 

 that artificial conditions very frequently bring about the hatching 

 of such animal germs as those of the polyzoa etc. I detected fii-st 

 a filmy, grayish-white growth that seemed associated with the de- 

 tached gemmules which lay in the groove around the bottom of the 

 jar. A gray, featureless growth at first, then spicules were seen, 

 in slightly fasciculated lines, attached to the glass and reaching up- 

 ward, then spreading out fan-like and branching. These were of 

 course, covered with sarcode, nearly transparent at first, and through 

 the filmy surfiice pores and osteoles could be detected with a pocket 

 lens. The latter were surmounted by the so-called "chimneys" or 

 cone-shaped extensions of the dermal film ; and through the apertures 

 at their summits effete particles could almost constantly be seen, puffed 

 out, as if thrown from a volcano and then blown off" by the wind. 



These products of single gemmules did not, as time passed on, 

 greatly increase in size ; possibly, because of deficient nutriment in 

 the unchanged water of the jar : but, crawling upward along the 

 glass to an average height of an inch or less, left the naked spicules 

 in place behind them as so many ladders or "stepping stones of 

 their dead selves" by which they had reached to "higher things." 

 ' Near the summit, one or more new gemmules would sometimes be 

 formed, after which the mother mass entirely disappeared. 



So much for the amount of growth from single gemmules. Where, 

 however, they were thickly sown, or germinated in situ upon the 

 stone, so that the contents of several could mingle and flow together, 

 the resultant sponge was very much larger. The mass, if it may be 

 so called, covered, at its best, nearly one third the surface of the jarJ 

 while those gemmules remaining upon the stone and amongst the 

 spicules of the old sponge, continued to germinate, to form abund- 

 ant sarcode and spicules, and, at least in one place, to throw out a 

 long unsupported branch or finger-like process, that ultimately 

 reached a length of two or three inches. 



Of course it Avas impossible to bring the higher powers of a com- 



