Mr. H. J. Carter on the Growth of Stromatopora. 103 



ferent from the matrix in which they are enveloped, after 

 the manner of Batter shy a &c., but not as regards an equally 

 "coral " nature of the tubes, as will be seen hereafter ; and, 

 if this view be right, then, by eliminating Caunopora from 

 the Strom atoporidae, much will be gained by the latter in 

 simplification. Still Rosen's general division of the struc- 

 ture of the Stromatoporw into " curvilinear " and u recti- 

 linear " coenenchyma will remain the same ; and the remark 

 in my paper (I. c. p. 312), that in Caunop>ora I saw the same 

 kind of granulated curvilinear fibre as in the coral called 

 Battershya, becomes intelligible. 



That the tubes of Caunopora are adventitious or different 

 from the curvilinear ccenenchyma of Stromatopora, which 

 generally accompanies them, is proved by their occasional 

 presence in another kind of Stromatoporoid coenenchyma, i, e. 

 in Stromatopora elegans, Rosen (vulg. " Stagshorn " here- 

 abouts), of which I possess two specimens ; while, in support 

 of this, Mr. Champernowne states that the stromatoporoid 

 coenenchyma of Caunopora is "as variable as the Stromato- 

 pora itself is variable ; " add to this that the different kinds 

 of coenenchyma constantly occur vnthout the tubes peculiar to 

 Caunopora. 



Further, it happens that in a polished section of a specimen 

 of Caunopora from " Pit-Park Quarry," which Mr. Champer- 

 nowne gave me, the lower surface (which is in its natural state) 

 is terminal ; that is, the tubes do not pass through it, while 

 at the bottom of the polished part, close to the angle it forms 

 with the " natural surface," the tribes may be observed to 

 turn out of their vertical course and become united to a hori- 

 zontal tortuous tubulation simulating that of the hydrorhiza 

 of hydroid zoophytes, which, under this aspect, appears to 

 form the whole of the " natural surface ;" and hence the ends 

 of the tubes of the Caunopora do not project through this 

 matted structure, as in most cases where the fractured part 

 of the specimen has passed through the tubes themselves. 



If this should be substantiated, then we can understand 

 how the tubes of Caunopora, for the most part, should be 

 without walls, *. e. appear as mere spaces, seeing that, while 

 one kind of Syringopora was probably a calcareous hydroid, 

 the tubes of Caunopora might, for the most part, have 

 belonged to a chitinous or flexible kind, which in fossilization 

 would only be represented as a mould made by the coenen- 

 chyma of the Stromatopora. Still, as Mr. Champernowne 

 observes, " crystallization, we know, acts, apparently, in the 

 most capricious manner, and it may be the cause of these 

 different aspects." 



8* 



