Geological Society. 229 



Carboniferous-Limestone series, whereas in Belgium and elsewhere 

 the range of this genus was more extensive. 



It was shown that in Diphyplnillum reproduction took place both 

 by fissiparity and by calicular gemmation, examples of both forms 

 being cited. It was also pointed out that the development of central 

 vertical plates, showing a tendenc}' to a passage into Lithosfrotion, 

 was due to the corals having lived in a sea periodically affected by 

 the influx of sediment from the neighbouring shore. 



After a history of the views held by different writers since Lous- 

 dale, and especially by M'^Coy, Milne-Edwards and Haime, Hall, 

 Billings, and De Koninck, on corals referred to this generic type, the 

 author gave a description of the species found in North Britain ; 

 and after pointing out their dilfereuces, showed that all exhibit 

 a tendency to vary, and that, if a sufficient series were available, 

 a passage might be traced not only between the different species, but 

 between DiphyphyJlam and the various allied genera. 



April 7, 1886.— Prof. J. W. Judd, F.R.S., 

 President, in the Chair. 



The following communications were read : — 



1. " On a Lower Jaw of Macluprodus from the " Forest-bed," 

 Kessingland." By James Backhouse, Esq., F.G.S. 



The Author believed that hitherto no example of a lower jaw of 

 Machcerodus has been met with in this country ; he consequently gave 

 a detailed description and measurements of a right mandibular 

 ramus obtained by him from the Forest-bed at Kessingland, in 

 Suffolk. Owing to the imperfect condition of the incisors and 

 canines, it was impossible to say whether these teeth were serrulated 

 or not, and consequently it was uncertain whether the bone belonged 

 to Macluerodus cuUridens or 31. latideiis. 



2. " A Contribution to the History of the Cetacea of the Norfolk 

 " Forest-bed." ■" By E. Tulley Newton, Esq., F.G.S. 



This paper was principally devoted to the description of two 

 fossil specimens. The first of these was a tooth, shown by external 

 and microscopical characters to have belonged in all probability to 

 the Sperm-whale, Physeter macroeephalus. The specimen was ob- 

 tained by Mr. Clement Reid, at Sidestrand. The second fossil, also 

 from Sidestrand, and now in the possession of Mr. James Backhouse, 

 consisted of the right half of the seven anchylosed cervical vertebrae 

 of a species of Balcena. The specific determination was less certain 

 in this case ; but the form approached most nearly to that of B. 

 biscayoisis. Of other vertebr* from the Forest-bed, one, a caudal, 

 was referred to Balana ; another, from the lumbar region, to 

 Balctnoptera. 



