174 Eevieivs — R. P. Whitfield — Carboniferous Crinoidea. 



variety of Waagen's genus Hemipty china, type B. Davidsoni, sp. nov., 

 Hall, from the Carboniferous limestone of Nova Scotia. Hall's old 

 genus Tropidoleptus, 1859, maintains its position as a Terebratuloid 

 and is now regarded "as an early representative of the important 

 family of the Terebratellidce." 



The exact relations and origin of those overgrown plicated 

 Centronelloids from Bolivia, three inches and a half long, which 

 were named Scaphiocoelia by their describer, Whitfield, remain 

 obscure, and the origin of the gigantic Stringocephalae is still veiled 

 in mystery. The latter, so abundantly developed in the Middle 

 Devonian of England and Germany, have been recently discovered 

 in the same horizon by Whiteaves in the Mackenzie Kiver Basin of 

 British North America. 



The systematic position of the genera Eichwaldia, AtdacorhyncJius 

 the authors leave undetermined. Lyttonia, Oldhamina, and Bich- 

 thofenia are somewhat doubtfully regarded as PalEeozoic forms of 

 the family Thecididce. 



Here terminate the authors' valuable generic discussions upon 

 the Palgeozoic Brachiopoda ; some of the results of their critical 

 researches have been already tabulated in Mr. Charles Schuchert's 

 " Classification of the Brachiopoda." A final chapter on the vexed 

 question of the classification of the genera is, however, promised by 

 Professors Hall and Clarke, to be issued with the requisite indices to 

 the second volume and sixty quarto plates (from xxi. to Ixxxiv. in- 

 clusive), thus completing this great undertaking. Its appearance 

 is awaited with interest as the coping-stone to a monumental work 

 which, taken as a whole, must be regarded as the most suggestive 

 and important production of the century concerning the general 

 History of the Brachiopoda. It forms the natural outcome and 

 most important manifestation of the value of the methods of the 

 correlations of Ontogeny and Phylogeny ^ as practised by Hall, 

 Clarke, Deslongchamps, Beecher, and the (Ehlerts, It is mainly 

 from the results obtained by these combined lines of research that 

 we owe the enlargement of our knowledge of the evolution of the 

 Brachiopoda — a progress too real and stable to be denied by any 

 serious student of the recent literature of this group of organisms. 

 To this subject we hope before long to revert. 



Agnes Crane. 



II. — Lower Carboniferous Crinoidea from the Hall Collection 

 NOW IN THE American Museum of Natural History, with 

 Illustrations of the Original Types. By R. P. Whitfield. 

 " Memoirs of the American Museum of Natural History," 

 Yol. I. Part I. 4:to. pp. 1-37, three Plates. 1893. 



THIS, the first number of a new series of Memoirs of the 

 American Museum of Natural History, is devoted by Mr. R. 

 P. Whitfield, Curator of Fossil Invertebrata in the Museum, to a 



1 The most recent addition to our knowledge of this suhject was a contribution by 

 Dr. C. E. Beecher to the American Naturalist for July, 1893, entitled, " Some 

 (Jorrelations of Ontogeny and Phylogeny in the Brachiopoda." 



