738 NATURE [MAY 17, 1930 which lie in the embrace of the river's curve. To this fact we know more of the central nervous syHtem the unwary visitor, the:,;e appear attractive for of many fossil animals than, for example, of their residence, or at the least for the week-end bunga• intestines, but to interpret the data with accuracy low, but are in fact unfitted for any dwelling-place. we must begin by studying in recent animals the The ground is always waterlogged at a level relations between the brain and the form of the little below the surface and is in most cases liable endocranial cavity, which is in many cases much to flood, so that the site is unhealthy for the occu• more spacious than would be necessary to contain pant. A still more important drawback is the the brain only. These and other methodical and difficulty of providing for disposal of sewage and technical matters are discussed in detail and of preventing contamination of the river. It is elucidated with many illustrations in the general needful, moreover, that the river should be allowed part (pp. 9-100) of the book. to spread over these meadows in seasons of heavy Dr. Edinger has t;ried to write a clear and rain, thus preventing sudden and exce,;sivc rise instructive book for neurologists, for whom so many of level in the lower reaches. names of geological periods and fossil animal-; are When we turn from the hygienic to the u:,sthctic mere ' wordH ' as well as for palmontologists not aspect of the matter we find that it is a requirement versed in the neurological 'jargon ' ; and in this of scenic grouping, or ' landscape composition ', she has been successful. to keep these broad, flat meadows free from build• The other part of the book is a copiously illus• ings, for they are the foil of riverside towns and trated critical compilation (classified according to wooded bluffs, and also essential to the prospect the zoological system) of all that is known about from the opposite, higher bank, from which we the central nervous system of fossil vertebrates ; obtain the wider view of tho Thames Valley and and it is more than a compilation only, for the its background of distant hills. author, guided by her great experience on the sub• The Council for the Preservation of Rural Eng• ject, often gives her own interpretation of the facts. land has only been in existence for three years, The alphabetical bibliography (250 entries!) has but its influence upon public opinion is already so the practical feature that not only arc the titles great that there is every reason to hope that the cited, but also with every article a brief mention is proposals put forward on behalf of its Thames made of what it contains referring to the subject Valley branch will receive careful and sympathetic in question. consideration. VAUGHAN CORNISH. In conclusion, some of the problems of general interest dealt with in the chapters may be men• tioned. Marsh's 'law' suggesting that the species Fossil Brains. that proved to be the ' fittest to survive ' had Diefossilen Gehirne. Von Tilly Edinger. Pp. 249. comparatively larger brains than the extinct forms, (Berlin: Julius Springer, 1929.) 36 gold marks. is not generally confirmed. Technical master• rrHE best results in science have been obtained pieces of palreoneurology are the reconstructions of - mostly by combining two hitherto separate the endocranial cavity with all canals and openings branches or methods. The author of the work in fossil fishes, made by Stcnsio. It is confirmed before us is a daughter of the late Prof. Ludwig that some of the giant forms among fossil animals Edinger, who is well known as one of the founders had small brains, but, a rdatively giant hypophysis. of the comparative anatomy of the brain. She The sacral dilatation of the spinal canal in Stego• grew up, therefore, in a very centre of comparative saurus is discussed in detail. The brain of the neurology, and having also studied pal:nontology flying reptiles (Rhamphorhynchoidea and Ptero• from the geological point of view, she joined these dactyloidea) had many bird-like features, while the two branches in a remarkable manner in palceo• brain of the contemporary Archceopteryx was still neurology, which is not an entirely new combina• more of the reptile type. The typical form of the tion, but has never been practised so thoroughly bird's brain seems to be in connexion with the and methodically. The chance to make errors in function of flying. Like other organs also, the this field is greater than anywhere else. For, as fossil brains make it clear that both birds and the author acknowledges in the very beginning of mammals have developed gradually from reptiles ; her book, a fossil thigh-bone is a thigh-bone anyhow, this evolution is partly a relative increase of the but a ' fossil brain ' is not a brain at all : it is-• fore-brain. The brains of fossil Anthropoidea are with a few exceptions-only a natural (petrified) described in a special chapter. or artificial endocranial cast of a fossil skull. By P. J. VAN DER Ii'EEN, JR. No. 3159, VoL. 125]