GENERAL HISTORY. 5 



MontictUipora by D'Orbigny, but apparently at a somewhat 

 later date, an important paper was published by 

 tinu°ecL°"' M'Coy on "Silurian Radiata" (Ann. Nat. Hist, 

 sen 2, vol. vi. p. 282). In this memoir Professor 

 M'Coy founded the genus Nebulipora, with the following 

 definition : — 



" Corallum encrusting or forming lenticular masses, with a 

 concentrically wrinkled epitheca below ; composed of small 

 prismatic tubes, perpendicular, or nearly so, to the upper 

 surface on which they open ; among the small tubes are 

 regularly arranged clusters of similar tubes of rather larger 

 size. All the tubes in contact, traversed by horizontal dia- 

 phragms at regular distances (walls apparently perforated by 

 rows of small foramina)." The species described under this 

 head are Nebulipora cxplanatay M'Coy, A'", lens, M'Coy, and 

 N. papillata, M'Coy, all from the Silurian rocks. I have 

 never had the opportunity of examining authentic specimens 

 of any of these forms ; but the descriptions given of them, 

 and the subsequently published figures (Brit. Pal. Foss., PI. I. 

 c), prove beyond a doubt that they belong to Monticulipora, 

 D'Orb. Under these circumstances, the genus Nebulipora, 

 M'Coy, must be taken as a synonym of Montictdipora, D'Orb., 

 in spite of the fact that it was scientifically and recognisably 

 defined, which certainly cannot be said of the latter. The 

 only ground (presuming that Moiiticulipora, D'Orb., really 

 was published first) upon which Nebulipora could be re- 

 tained, would be its possession of perforated walls to the 

 corallites ; but this observation was only put forward doubt- 

 fully by M'Coy, and there can be little doubt that it is with- 

 out a basis in fact. 



In 1850, Professor King described a coral from the Permian 

 rocks of England (Mon. Perm. Foss., p. 28) under the name 

 of Steiiopora coluninaris, Schloth., which may possibly be a 

 MonticiUipora. This is of interest, as it is questionable if we 

 can as yet definitely assert that we are acquainted with any 

 species of Monticulipora from deposits later than the Car- 



