﻿Cryptozoon and other Ancient Fossils. 217 



prefers to regard Arclueocyathus as a coral, though he 

 admits that it is of a very ])eculiar and generalized type, 

 unknown except in the lowest Cambrian ; but there very 

 widely diffused, since it occurs in different parts of North 

 America, in Spain and in Sardinia. I think, however, we 

 may still be allowed to entertain some doubt as to its 

 reference to corals, more especially as its skeleton does 

 not seem to have l)een composed of aragonite. I still 

 continue to hope that, whether Protozoon or coral, it may 

 be traced below the Lower Cambrian, and may form a 

 link connecting the fauna of that age with that of still 

 older deposits. In my description of it in " The Dawn of 

 of Life," in 1875, I have written of it in the followdng 

 terms : — " To understand Archasocyathus let us imagine 

 an inverted cone of carbonate of lime, from an inch or 

 two to a foot in length, and with its point buried in the 

 mud at the bottom of the sea, while its open cup extends 

 upward into the clear water. The lower part buried in 

 the bottom is composed of an irregular acervuline net- 

 work of thick calcareous plates, enclosing chambers com- 

 municating with one another. Above this, where the cup 

 expands, its walls are composed of thin outer and inner 

 plates perforated with numerous holes in vertical rows, 

 and connected with each other by vertical partitions, also 

 perforated, establishing free communication between the 

 radiating chambers, into which the thickness of the wall 

 is divided." Such a structure might, no doubt, serve as a 

 skeleton for a peculiar and generalized coral, but it might 

 just as well accommodate a protoplasmic protozoon with 

 chambers for its sarcode and pores for emission of its 

 psendepods both outwardly and by means of the interior 

 cup, which in that case would represent one of the 

 oscula or funnels of Eozoon or of the modern Carpenteria. 



