Mr. T. R. Jones on some Foraminifera from Chellaston. 85 



its filling up, and of the extension of London Clay and Lower Ter- 

 tiary deposits to a more northerly point than had previously been 

 ascertained. 



3. "On some Foraminifera from the Upper Triassic Clays of 

 Chellaston, near Derby." By T. Rupert Jones, Esq., F.G.S., and 

 W. K. Parker, Esq., M. Micr. Soc. 



Bluish-grey specimens of the mottled clay from the pits at Chel- 

 laston, 3 miles south of Derby, whence the alabaster is obtained, 

 yielded abundance of minute Foraminifera, a few Entomostraca 

 (Cy there), some Otolites, and spines and plates of small Echinoderms, 

 together with fine siliceous sand and pyritous granules. Of the 

 Foraminifera nearly one-half consist of a small variety of Rotalia 

 repanda, namely R. elegans, D'Orb. The next most numerous 

 group are the Nodosarince, including varieties of Nodosaria, Denta- 

 Una, Marginulina, Vaginulina, Planularia, Frondicularia, Flabellina, 

 and Cristellaria. The genus next in numerical force is Nubecularia. 

 Polymorphina, Bulimina, and Lituola are represented by a few indi- 

 viduals. 



The authors stated that nearly all the varieties of the Nodosarince 

 found at Chellaston are present in the Lias, in the clays of the 

 Oolites, in the Gault, Chalk- marl, Chalk, some Tertiary deposits, 

 and in some of the muds of the western Mediterranean and other 

 seas ; and the species of the other genera have also persisted to the 

 present day. One of the Triassic forms was described as a new 

 variety under the name of Planularia pauperata. It is found also in 

 the Oolite and in the recent seas. The authors also entered at some 

 length into the history of the genus Nubecularia, and described a 

 new elongated variety under the name of N. Tibia. After describing 

 the distribution of Foraminifera in many of the Mesozoic strata, and 

 pointing out that Nodosarice, Textularitf, Rotalice, and some other 

 Foraminifera occur in the palaeozoic rocks, Messrs. Jones and Parker 

 observed that altogether we have here some remarkable instances of 

 the persistency of life-types among the lower animals. " Though the 

 specific relationship of the palaeozoic Foraminifera require further 

 elucidation, we feel certain that the six genera represented in the 

 Upper Keuper Clay of Chellaston by at least 30 varieties stand 

 really in the place of ancestral representatives of certain existing 

 Foraminifera, — that they put on their several subspecific features in 

 accordance with the conditions of their place of growth, just as their 

 posterity now do, and that, although we have in this instance met 

 with only the minute forms of a 700 fathoms mud-bottom, yet else- 

 where the contemporaneous fuller development of these specific types 

 may be found by careful search in other and more shallow-water 

 deposits of the Triassic period." 



May 2, I860.— L. Horner, Esq., President, in the Chair. 



The following communications were read : — 



1. "On the Physical Relations of the Reptiliferous Sandstone 

 near Elgin." By the Rev. W. S. Symonds, F.G.S. 



Referring to Sir R. Murchison's sections of the Elgin district, 

 published in the Quart. Journ. Geol. Soc. No. 59, pp. 424 and 428, 



