ON BUDDING IN ANIMALS. 7 



Again, he found that if a piece of Tubularia was suspended 

 in the water horizontally by the middle, it produced a head at 

 each end. It is interesting in this connection to remark that 

 Cerianthus, one of the anemones frequenting sand, gives off 

 tentacles from the aboral margin of a wound of the body-wall. 



It is worthy of note that in the phylum of Echinoderms bud- 

 ding is generally absent from the adult as a normal mode of 

 increase, though it is well known that renewal of lost parts is 

 very general, a disk regenerating arms and a detached arm 

 reproducing a disk and other arms. Yet in Linckia (Ophidiaster) 

 multifiora buds arise from the tips of the rays. The regularity 

 of their stellate bodies and their brittle nature do not seem to 

 favour this method of development, though there may be other 

 and more occult causes. In the young condition of several 

 members of the group, however, the rudiment of the adult is 

 budded off from a remarkable larva (Echinopoediam), or from a 

 reptant form (as in Cribrella). These larvae therefore contain 

 within them the germ-plasm from which the adult is formed, 

 and which at a certain stage develops, while the larvae them- 

 selves disappear. The adult is thus in one sense a bud of the 

 larva, and the one is indispensable to the other, for no bud 

 could be formed if the larvae were swept off at an early stage. 

 Such types therefore appear to encounter a double series of 

 dangers — first as larvae which never attain the adult state, and, 

 secondly, as minute buds from the former, which have to pass 

 through early and precarious stages before reaching the adult 

 form. It has to be borne in mind, however, that in many the 

 larval stages are pelagic while the adults live on the bottom, so 

 that the conditions of life are very different. Nevertheless, 

 some might suppose that it would have been sufficient for such 

 forms to have sprung directly from eggs — pelagic or otherwise — 

 without the foregoing complex larval stages — for example, that 

 resembling a painter's easel, with its remarkable spicular 

 skeleton. . Such may have arisen from the necessities of its 

 surroundings, which thus, it may be supposed, caused the pro- 

 duction of the larva which by and by took the form of a painter's 

 easel, and then developed a bud which assumed the adult out- 

 line, and settled on the bottom. In the same way it is not easy 

 to see what advantage the common Cross-fish could have gained 



