192 ZOOPHYTES. 



in the genuine sense of the word : the length of the stem is many hun- 

 dred times its diameter, thence the presence of the liquid element alone 

 supports it erect, and even then, the higher portion of the tallest, tends to 

 overbear the rest. 



Propagation. — After my earlier observations had been conducted 

 during several years, their progress was interrupted by an obstacle of too 

 repeated recurrence, a deficiency of specimens. I found it impossible to 

 obtain any. During the preceding period, all the vesicles I had seen re- 

 sembled a vase with a spinous prolongation, very distinct. — Fig. 5. After 

 a long interval, several luxuriant specimens reached me on April 6, which 

 were from 8 to 12 inches in height. The branches of some of them were 

 yielding under a vast profusion of vesicles, resembling minute oranges. 

 But, unlike the former spinous kind, they were of compound formation, 

 consisting of a hollow pedestal, surmounted by a sphere about three times 

 its diameter : and on the whole, bearing much resemblance to the com- 

 pound vesicle of the Sertularia abietina, above described. Some spinous 

 vesicles, together with some ampuUate or flask-shaped, were present be- 

 sides. 



A number of the compound vesicles now contained one, two, three, 

 or four spherical yellow corpuscula, very conspicuous, both in form and 

 colour, through their diaphanous enclosure. None had more than four, 

 many were empty, and hardly discernible, from transparence amidst the 



water. — Fig. 6. 



A vesicle subjected to the microscope, exposed four internal corpus- 

 cula, one ovoidal, which betrayed symptoms of animation ; the other three 

 globular and still inert. The former relaxed still more as an ovoid, it be- 

 gan to move, then shifted its position in the vesicle, where there is always 

 a considerable vacuity. On directing the microscope to another vesicle, 

 the contents proved to be much farther advanced : three yellow animals, 

 all mature, lay parallel to each other within it. One began to move : it 

 glided slowly upwards to the circular orifice, which opens the summit of the 

 sphere, from whence, protruding its head as if searching around, it dropped 

 down among the surrounding element. The second, by a similar course, 

 followed its precursor, within a minute, and dropped down also. Next, 



