G. ADEQNA. 237 ^ 



in the preserved specimens brought to Europe no rind 

 has been discerned, yet it is by no means certain that 

 when fresh, and in a living state, they do not possess a 

 rind. Supposing that these beings do not change by 

 desiccation, we must admit that Australasia, in these 

 Polypidoms, offers us anew example of organised be- 

 ings which have no place in our classifications, a cir- 

 cumstance not rare in that fifth division of the world. 

 The difference between the fan-formed expansion and 

 the stem is so great, that naturalists at first sight 

 were tempted to look upon these two parts as distinct 

 beings ; it is however easy to prove that they belong 

 to the same animal. Peron, who had seen them in 

 the very site of their growth, told me he had frequently 

 convinced himself that they were one and the same 

 Polypidom. If the base of the fan-formed expan- 

 sion of the Adeonas be attentively observed, it may 

 be seen to extend itself into the stem, and only by de- 

 grees to change its nature : when that change is com- 

 pleted in the stony articulations, we find this same 

 stony substance forming the expansion, which differs 

 only from the articulations in possessing cells that 

 are not found in the stem. These circumstances are 

 sufficient to prove that the stem and the expansion 

 of the Adeonas, notwithstanding the disparity of their 

 form, cannot be the productions of different ani- 

 mals. 



The stem of this Polypidom is irregularly cylin- 

 drical, sometimes branching, and composed of calca- 

 reous articulations without pores or cells, as hard as 

 coral, and separated from each other by disks or 

 plates of a horny, fibrous, and flexible substance. The 



