ii6 TABULATE CORALS. 



demonstrated by Rominger, proves that it is properly referable 

 to the Favositidce, among which its true place would seem to be 

 in the neighbourhood of Vermipora, Hall. It differs from the 

 latter, in fact, principally by the lax spreading mode of growth 

 of the corallum, and by the much greater extent to which the 

 corallites are disconnected from one another. 



Dr Rominger has described a species from the Niagara Group 

 of North America {loc. cit., p. 71); but I am only acquainted 

 personally with the type-species, R. umbellifera, Bill., of which 

 I subjoin a short description. I regret, however, that the state 

 of preservation of my specimens is such — owing to silicifica- 

 tion — that I have been unable to procure satisfactory micro- 

 scopic sections, and that I can therefore merely give such 

 characters as can be learned by the ordinary methods of 

 examination. 



Romingeria umbellifera, Billings, sp. 

 (Fig. 19.) 



Aulopora umbellifera, Billings, Canad. Journ., new sen, vol. iv. p. 119, 



fig. 21. 

 ,, umbellifera, Nicholson, Report on the Palseontology of Ontario, p. 



43, PL VI., fig. 4 (poor figure). 

 Quenstediia umbellifera, Rominger, Rep. Foss. Cor. Michigan, p. 70, PI. 



XXXIIL, fig. 3. 



Spec. Char. — Corallum erect, lax, spreading, of cylindrical 

 corallites, with a thick annulated wall, adorned with fine en- 

 circling striae. Diameter of the corallites about one line. The 

 primary stems remain undivided for a distance of a quarter of 

 an inch or more, and then give origin to a cluster of corallites 

 in an umbellate manner, one or more of these proceeding to 

 proliferate in a similar manner, and at a similar interval, and 

 the process being repeated till a loosely fasciculate corallum Is 

 produced. The number of corallites in a single verticil varies 

 from five or six to as many as ten or twelve, and they are at 

 first closely in contact with one another, the union of their 

 walls often extending to a distance of two or three lines from 



