224 EDMUND I',. WILSON. 







develop into a fully developed polyp. None of these cases lived 

 more than six days, but in one of them the exhalent zooid had 

 very considerably enlarged. This may, however, have been a 

 merely passive expansion, and I regret that no decisive result 

 was reached. Repetition of Torrey's experiment of cutting the 

 colony diagonally across at an angle of 45 gave a suggestive 

 but not quite conclusive result. The best case obtained is shown 

 in Fig. 4, the section being in such a plane as to leave one of the 

 primary lateral buds (a, </) in each piece, the posterior piece 

 having in addition four smaller buds and the anterior one six. 



o 



Within an hour after the operation, and while the wounds were 

 still widely open, a complete readjustment had occurred in the 

 relative position of buds, and after twelve hours the wounds 

 were entirely healed. The large lateral bud (c/) of the posterior 

 piece was so displaced as to be directed straight forward, giving 

 exactly the appearance of an axial polyp (Fig. 4, ), while by a 

 corresponding process in the anterior piece the lateral bud (a) 

 was directed straight backward (4, Z>). In the course of 48 

 hours however a rapid formation of new tissue took place in 

 both pieces, forming the beginning of a new axial polyp in the 

 posterior piece (4, F) and of a new peduncle in the anterior one 

 (4, C). At the end of seven days the new axial polyp of the pos- 

 terior piece (4, G, .r) was fully formed though still not quite as 

 large as the original lateral one, with four pairs of tentacular 

 pinnules, and a median dorsal bud had appeared exactly in the 

 position of the exhalent zooid. When the colony was fully 

 expanded the new axial polyp was directed almost straight for- 

 ward while the original lateral bud (d] was swung quite over to 

 one side, nearly in its original position, though the colony still 

 showed a very marked asymmetry. At the end of seventeen 

 days the axial polyp was as large as the lateral one, but no other 

 essential change had occurred. The colony was at this time 

 killed for preservation, since I was compelled to leave Beaufort ; 

 but the evidence of the specification of the buds obtained from 

 this and the other cases described renders it probable that the 

 original condition would ultimately have been restored and that 

 the primary process of moulding would in the end have been 

 wholly overcome by the regenerative process. In the meantime 



