ON MINERAL VEINS IN CARBONIFEROUS LIMESTONE. 377 



in shape the more simple Conodonts ; but that against this view was the fact 

 that no shells of Entomostraca or other crustaceans had ever been found 

 in the Conodont beds, and that it was improbable therefore that they could 

 have belonged to an organism as susceptible of preservation as their own 

 substance. Although I may agree with the opinion of Professor Owen, that 

 these bodies do not belong to Entomostraca, I do so for other reasons. In 

 the first place, although his remarks may apply to the SUui-ian Conodonts, 

 he is wrong in supposing that they do not occur in the same beds with 

 Entomostraca ; for it happens that most of my specimens from the Carboni- 

 ferous Limestone are found in beds crowded with Entomostraca, which occur 

 also in the lead-veins, these two sources having yielded me about 40 species. 

 The great variety my series of Conodonts presents is decidedly against refer- 

 ring them to Entomostraca ; and what is, I think, suiRciently conclusive is 

 the fact that they are usually of greater size than the crustaceans, to which 

 they would thus be attached. The conclusion to which he arrives respect- 

 ing them is, that they were united to a soft perishable body, and that 

 they have most analogy with the spines, booklets, or denticles of naked 

 MoUusks and Annelides. There is no doubt great difficulty attending their 

 elucidation, and the above view, though not, I think, quite satisfactory, 

 appears as probable as any other that has been advanced. One objection to 

 it is the variety of forms they present, and that we have no existing ana- 

 logues. To whatever they belonged, the creatures yielding them probably 

 passed away with Palasozoie times, as I have found no trace of them in my 

 examinations of any later deposits. It has always been my object, when 

 seeking them in the Carboniferous Limestone, to find their association with 

 some other organized body, but in this I have always failed. They invari- 

 ably occur as separate detached specimens, and without any arrangement as 

 regards one another. 



Entomostraca.— The bivalve Crustacea included in this family, although 

 not individually numerous, are present in nearly every vein I have exa- 

 mined. They have been in the hands of my friend Professor Rupert Jones, 

 who has provisionally determined about 29 species from the veins, including 

 those of Charterhouse and Weston, the great majority of which are new. 

 They include the genera Bairdia, Beyrichia, Cythere, Cytherella, Kirkbia, 

 and Moorea, the genus Cythere alone having as many as seventeen species. 



Foraminifera . — Oui' knowledge of some of this very beautiful class of 

 microzoa will be considerably extended by those I have been fortunate 

 enough to obtain from the lead-vein deposits. This will especially apply to 

 the genus Involutina, which until lately was chiefly known by a single 

 species of/, liassica, Jones, sp., many specimens of which I have found in 

 the Liassic deposit in Charterhouse Mine. More recently M. Terquem's 

 researches in the Lias of the north-west of France have brought to light 

 several new forms belonging to the same type, four of which, viz. I. poly- 

 morpTia, I. aspcra, I. silicea, and /. nodosa, all supposed to belong to the 

 secondary age, are represented in my gatherings from the Carboniferous- 

 Limestone veins. My series not only carries back the above secondary species 

 to deposits of Palaeozoic times, but associated with them are nine others, so 

 that under these peculiar conditions there are not less than fourteen species of 

 this hitherto little-known genus. Bentalina pauperata, D'Orb, a now living 

 species, which has been traced back through Tertiary, Liassic, and Permian 

 formations, not only in this series goes back to the Carboniferous Lime- 

 stone, but I have also obtained it in the "VVenlock shales, an evidence of a 

 delicate microscopic shell having existed through a long series of ages to our 



1869. 2 c 



