340 Mr. H. J. Carter on Stromatopora dartingtoniensis. 



tubes have not the internal structure of Syringopora, but 

 are hollow, and therefore cannot belong to that genus " 



His original statement, however, best accords with the 

 observations I made last year (before I knew what Dr. Roemer 

 had published in 1844, ' Das Rheinische Uebergangsgebirge,' 

 p. 57), viz. that Mr. Champernowne had shown me speci- 

 mens of the so-called cyathophylloid coral (Battersbya) and 

 Syringopora, respectively enveloped in Stromatopora, like 

 the tubes of the so-called Caunopora (' Annals,' vol. iv. 

 p. 102). 



Again, these "tubes," although often apparently "hollow " 

 (from the homogeneous crystalline character of the calcspar 

 filling them), as stated by Dr. Roemer, yet sometimes, as 

 my specimens show, present not only infundibuliform tabula?, 

 like those of Syringopora, but horizontal ones like those in 

 Millepora alcicornis } as figured in 1877 (' Annals,' vol. xix. 

 pi. viii. figs. 21-23) — a combination in Syringolites Tiuro- 

 nensis, Hinde, to which Dr. G. Steinmann has lately called 

 attention as " scarcely" differing from Syringopora infundi- 

 bulifera, Goldf. (Neues Jahrbuch f. Mineral. Geol. u. Palaont. 

 Jahrgang 1880, Band i. p. 435, with illustration) ; hence 

 Roemer's original statement might not have been altogether 

 wrong. Still I have one specimen from " Pit-Park Quarry " 

 in which the Stromatopora surrounding a Cyathophylloid 

 coral is so densely charged with Aulopora repens, var. minu- 

 tula, Goldf., that it appears unmistakably, weathered out on 

 the surface, in its genuine double branching form. 



Caunopora, therefore, having been found to be no genus, 

 but a compound of Stromatopora and Aulopora repens, renders 

 (as I have before stated) a description of Stromatopora much 

 more simple, which is thus reduced to the basal structure 

 and the stellate venations, in the larger branches of which I 

 have lately found the tabula? which it is my object now to 

 describe. But before doing so it is also desirable that we 

 should first direct our attention to the nature of " tabula? " 

 generally, and then as they appear in the tubular spaces of 

 that living organism which is the nearest yet found to Stroma- 

 topora, viz. Millepora alcicornis. 



The term " tabula? " has been given to those portions of 

 the coenenchyma which traverse the tubular structure of the 

 so-called " Tabulate Corals " (ex. gr. Favosites). They are 

 formed pari p>assu with the growth of the tubes that in juxta- 

 position follow a concentric laminated development of the 

 coral, which is thus made up of them, so that in a vertical 

 section the tabula? appear to correspond with the lamina? of 



