1894- SOME NEW BOOKS. 219 



nately used to denote an individual variation within a species as well 

 as climatic or geographical races. We, therefore, to avoid all possible 

 errors, have determined to discard the term variety altogether. 

 To denote individual variations we shall employ the word aberra- 

 tion, and for geographical forms which cannot rank as full species, 

 the term sub-species." 



The present number contains communications from the three 

 editors, from Dr. Forsyth Major and Mr. W. F. Kirby, which are 

 written in Latin, German, or English. Nothing is said as to 

 language, but we hope Mr. Rothschild's catholicity will not include 

 Russian or Japanese. Two of the plates are beautiful specimens of 

 the art of J. Smit and J. G. Keulemans. 



The Crinoidea of Gotland. Part i. The Crinoidea Inadunata. By F. A. 

 Bather. Kongl. Svcnska Vet. Akad. Handl. Bd. xxv., no. 2. 410. Stockholm: 



The Silurian beds of the Isle of Gotland have long been famous for 

 the wealth of numbers and excellence of preservation of their fossils, 

 ranging from the Upper Llandovery to the Upper Ludlow. Numerous 

 monographs have appeared upon them from time to time, for they 

 have yielded to the Swedish school of palaeontology its most profitable 

 material. The Crinoids have been elaborately figured in the great 

 folio " Iconographia Crinoideorum" of Professor Angelin in 1878; 

 and probably no one who has had occasion to use that work but has 

 felt that it is not a fair specimen of Swedish science ; the death 

 of the author before its completion probably accounts for many 

 of its errors. The unsatisfactory nature of Angelin's posthu- 

 mous monograph has been the more regretted owing to the singular 

 wealth and interest of the Gotland Crinoids. Students of 

 Echinodermata will therefore welcome the first of a series of 

 detailed memoirs on these fossils from the pen of Mr. F. A. Bather. . 

 This first part deals only with the Inadunata, the Order in which 

 all the brachials are free and the interradials do not take part in the 

 composition of the dorsal cup except in the posterior interradius. 

 The memoir consists of 200 pages, and 10 admirable plates, crowded 

 with instructive and artistic figures by Mr. Liljevall. With the 

 exception of a few introductory pages, which deal with the terminology, 

 bibliography, and stratigraphical horizons, it consists entirely of a 

 detailed account of the structure of the Crinoids, with discussions of 

 the alifinities and synonymy of the various species. The Inadunata 

 in the fauna comprise thirty-nine species sufficiently well known to be 

 described ; these are referred to ten genera, and the imperfection of 

 our knowledge of the Silurian Crinoids may be judged from the fact 

 that these ten genera are referred to no less than seven or eight 

 families. Of the species fifteen are new, and there is one new genus 

 appropriately named Gothocvinns. 



The present, however, is not a work to be judged by the number 

 of species created ; it is in its detailed dissections and figures, its 

 precision of nomenclature, the care that has been taken in determining 

 the morphological meaning of the different elements of the skeleton, 

 and the patience with which the nomenclature and synonymy have 

 been discussed, that its real merit lies. Forms such as Pisocrinus and 

 Calceocrinus, that have been previously turned upside down, wrong 

 side before, or inside out, to suit the varying explanations of their 

 describers, are now finally explained, owing to the recognition of the 

 anal tube. The curiously coiled Herpetocrintts is also now first satis- 



