1 62 TABULATE CORALS. 



lites are often separated from one another by an irregular 

 cellular coenenchyma, and that the walls of the tubes when 

 contiguous are not perforated by mural pores, though he gives 

 no drawings of the structure of the corallum which would sup- 

 port either of these statements. I cannot, of course, offer any 

 opinion as to the phenomena presented by Dr Rominger's speci- 

 mens, as I have not had any opportunity of examining them, 

 and I should not wish to dogmatise as to examples which have 

 not come under my direct observation. It must be borne in 

 mind, however, that the specimens in my possession are the 

 ones upon wJiich the genus was founded, and that they are there- 

 fore the types of the genus. These specimens have been sub- 

 jected to a careful macroscopic and microscopic examination, 

 and I can confidently affirm that they possess walls of an exag- 

 geratedly perforate type (as compared with Favositcs) ; that 

 their corallites are for the most part indubitably in contact, with 

 their walls absolutely fused with one another; and that any 

 interspaces which may here and there exist between the coral- 

 lites admit of being explained upon a different supposition than 

 that they are of the nature of " ccenenchymal tubes." The 

 drawings which I have given, being taken by the camera lucida 

 from microscopic slides, will sufficiently prove the accuracy of 

 these statements. 



A more difficult point to settle concerns the relations of 

 Columnopora to Calaposcia, Billings ; and as I have no speci- 

 mens of the latter, I shall here say the little that is necessary 

 concerning the curious types included by the eminent Canadian 

 palaeontologist under the above name : — 



The genus Calapcecia was defined by Mr Billings in the 

 'Canadian Naturalist' (2d sen, vol. ii. p. 425, 1857) as 

 follows : — 



" Corallum composite, forming hemispherical or subspherical 

 colonies. Corallites slender, tubular, perforated as in Favosites, 

 and with their outside striated by imperfectly-developed costse. 

 Radiating septa (in the species at present known) about twenty- 

 four. Tabulae thin, and apparently in some instances not com- 



