Bibliogi-aphical Notices. 413 



work on the Stalked Criuoids *. This monograph, the result of the 

 researches of Dr. P. Herbert Carpenter upon all the known recent 

 species, tlirew a flood of light upon the morphology of the long array 

 of fossil foims ; for although the number of living representatives of 

 the Crinoidea bears only the smallest proportion to those which are 

 extinct, the clue they furnish renders inestimable assistance in the 

 task of elucidating the organization of the primeval members of the 

 race. In comparison, the difficulties that beset the path of the 

 student of a group of animals known only as fossils, and of which 

 no distant relatives whatever have survived to the present day, are 

 immeasurably greater. 



We have now received a monogi-aph on the Blastoidea, another 

 group of Echinoderms, and one to which special interest attaches 

 from the fact that the type became altogether extinct before the 

 close of the Palaeozoic epoch. Not a single living representative or 

 analogue is known. On this account the Blastoidea are far more 

 difficult to study, and tho intricacies of their organization much more 

 perplexing to unravel, than is the case in the kindred class of the 

 Crinoidea, 



Owing to the strange human tendency to value most what is 

 rarest and most difficult to attain, the elucidation of the details of 

 Blastoid anatomy has long been a goal towards which the aim of 

 naturalists has been directed. It is somewhat surprising, however, 

 that although many detached observations and descriptions of species 

 have been published, no attempt at a complete monograph of these 

 obscure and imperfectly -known animals has been made since the 

 short but masterly memoir of Dr. Ferd. Roemerf in 1851. Much 

 material and knowledge has been accumulated in the interval. 



The present work is the result of seven years' constant and indus- 

 trious research on the part of Mr. Eobert Ethoridge, Jun., and 

 Dr. P. Herbert Carpenter. The previous publications of both authors 

 are too well known and appreciated to need recapitulation here, and 

 it may be unhesitatingly affirmed that the present investigation 

 could not have been placed in more competent hands. Mr. Etheridge's 

 extensive knowledge of fossil forms, and his carefully trained and 

 accurate judgment would alone be a sufficient guarantee for the 

 excellency of the work ; whilst his association with such a collaho- 

 rateur as Dr. Carpenter, who is without exception the most inti- 

 mately acquainted with the morphology of recent Criuoids of any 

 living naturalist, is a circumstance something more than fortunate. 

 The result is that a monograph has been produced of which British 

 naturalists may well be proud ; and the Trustees of the British 

 Museum are to be congratulated on the acquisition and publication 

 of a most important memoir. 



* "Report upon the Crinoidea collected during the Voyage of H.M.S. 

 ' Challenger' during the years 1873-76.— The Stalked Criuoids." By P. 

 Herbert Cai-penter, D.Sc. [Report on the Scientific Results of the 

 Voyage of H.M.S. ' Challenger.'— Zoology, part xxxii.] Published by 

 Order of Her Majesty's Government, 1884. 



t Archiv f. Naturgeseh. 1851, Jahrg. xvii. Bd. i.pp. 323-397, Taf. i.-v. 



