314 



THE GEOLOGIST. 



Such are the characters of Sowerby's type ; but it appears to have 

 varied considerably in different localities, and Professor de Koninck 

 is of opinion that his own 82^- crassa and M. Coy's Sp. grandicostata 

 are probably nothing more than well-marked varieties of Sowerby's 

 species. 



Spirifera convoluta is a very rare shell in England and Belgium, 

 and the principal object of this note is to present to the reader a 



correct drawing of the only perfect 

 example that has been, to my know- 

 ledge, hitherto discovered in Great 

 Britain, and which was kindly lent 

 to me by its possessor, J. E-ofe, Esq., 

 who found it in the carboniferous 

 limestone of Thomeley, near Chip- 

 ping, about ten miles north-east of 

 Preston, Lancasliire. This unique 

 example measures in length 11 lines, 

 in width 57, and in depth 12 lines; 

 and another imperfect specimen 

 (which the discoverer has liberally 

 added to my collection) must when 

 complete have possessed almost simi- 

 lar proportions. 



Professor de Koninck's decided 

 opinion is that Sp. convoluta differs 

 specifically from 8jp. hisulcata, and he 

 entirely agrees in this with the cele- 

 brated author of the " Geology of 

 Yorkshire ;" and it must be admitted 

 that a glance at the two shells is suffi- 

 cient to impress one with the peculiar 

 fusiform shape presented by Phillips's 

 species, which somewhat resembles a 

 weaver's spindle. I am therefore 

 disposed to waive the misgivings ex- 

 pressed, and to leave the matter as 

 stated at page 35 of my " Monograph." 



To the French translation of my 

 paper published in the eleventh num- 

 ber of The Geologist, in the present 

 year's volume of the " Transactions of 

 the Royal Society of Sciences of 

 Liege," Professor de Koninck has 

 added some very valuable notes, in 

 order to place in comparison mth my 

 British list of carboniferous species 

 possessed of calcified spiral supports, those which for many years 

 prior to 1843, and subsequently, had been discovered by him in the 

 corresponding Belgian strata. The analysis of these two catalogues 



