The Afi'imtii:s of Animals 



L'axatomie cumpauiîi:' dks Animavx Basée .sur L'embuyolooik. Par Louis Roule. 

 8vo. ))ii. xxvi + 197-2, with 1202 figures. Pan.-H : Masson et Cie. 1898. Piice 

 48 fraucs. 



MPv Eoule is Professor at the University of Toiilouse and is weJl 

 known by liis works " Eiiibiyologie générale" and "Embryologie 

 comparée," to wliich the two bulky tomes before us form a natural 

 sequel. The object of the book is not to give either a systematic 

 suminary of the whole animal kingdom, a detailed account of its 

 numerous variations of structure, or eyen an elaborate discussion of 

 selected types, but rather to show tlie relationships of animais and 

 thus to manifest évolution in the Animal Kingdom. As the chief 

 guide in determining those relationships, Prof. Eoule takes ein- 

 bryology, although palaeontology and comparative morphology and 

 histology are not rejected. 



The Animal Kingdom is divided into sixteen branches, dealt with 

 in the following order : Sarcodic Protozoa, CiUate Protozoa, Mesozoa, 

 Spongida, Uydrozoa, Scyphozoa, Platlielminthes, Nemathelminthes, 

 Trochozoa (llotifera ; Bryozoa, P>rac]iio])oda, Plioronidea, Sipunculidea ; 

 Mollusca ; Arhiannelida, Hirudin-a, Chaetopoda; P.seudannelida = 

 ,St«rnaspids & Echiurians), Arlhropoda. Chaetognatha, Peripatida, 

 'Echinodeima, f]nteropneusta, Tunicata, Vertebrata. Each of thèse 

 branches is dealt with under tlie following heads: General considéra- 

 tions and relations to otiier branches ; Distribution in nature ; General 

 organisation, first of the embryo, then of the adult ; Comparative 

 account of the différent body Systems, as manifested in the varions 

 Classes of tlie Branch ; Principles of classification, division into Classes, 

 and mutual relations of the Classes ; Bibliography. The second 

 volume ends with two indices, the first to the zoological names, the 

 second to the anatomical ternis. There is no gênerai chapter dealing 

 with the Animal Kingdom as a whole, or with the classification 

 adopted, since that was given in the préviens works refened to 

 above. 



Seeing that the subject is one of such obscurity, and open to so 

 wide diversity of opinion, it hardly seenis worth while pointing ont 

 the paths along which we should not care to follow our ]n-ofessorial 

 guide. That lie bas made the attempt, and that Messrs Masson hâve 

 published it, is alone a reason for gratitude. For the book, though 

 somewhat wordy, and occasionally less clear than we are accustomed 

 to^ from a Frenchman, furnishes a séries of very readable accounts 

 with many suggestions of interest. Witbout casting any slur on 

 embryological research, we inust confess to some distrust in those 

 who place quite as much reliance on it as does Prof. Pvoule. But taking 

 it at his valuation, we fail to see how it lends support to the view 

 that the Nautiloidea are ancestral to the Amnionoidea and tlie ad- 

 mittedly dibranchiate fornis ; for their embryology shows cleaily that 

 the Nautiloidea hâve lost an important structure, the protoconch, once 

 possessed by them and still possessed by the other orders. We also 

 venture to think that the known facts in' the embryology of récent 

 echinoderms afford no proof whatever that the five-rayed ancestor, 

 which the holothurians niust bave had in cominon with the other 

 classes, was less developed than many cystids. Prof. Roule's ' hypo- 

 t hetical Pentazoon ' is not the most ancestral form that is sliadowed 

 forth to us, either by embryology or by palaeontology. 



Spécial praise is due to the illustrations, which hâve nearly ail 

 been drawn for the work, under Prof. Poule's direction, by Mr L. 

 rlammes, in a style that is at once original and effective. We must, 

 however, protest against the picture on p. 1275, purporting to repre- 

 sent livhig crinoids, " dans un fond rocheux de convention" (penny 

 peep-show convention). Attached to one of thèse marvellous rocks, 

 by a stem far too short in projiortion to its anus, is a Pentacrinus; 

 how it is fixed one cannot tell, but certainly not bv the cirri, as 

 undoubtedly it would be in life. Below it, on a bottom that is 

 apparently muddy, is a Ifulopus, which certainly ought to hâve been 

 attached to the rocks, thougli not on the same page as the Pentacrinus, 

 of which genus there appear to l)e other sp(^cimens, wildly waving 

 about on a vertical précipice in the back'ground. Fortunately, this is 

 the only picture of the kind. The printing of the liook is excellent, 

 but the type and paper used hâve made the volumes rather too portly 

 for comfort. With the works of the two Perriers, of Delage and 

 Héronard, of Blanchard, with his corps of specialists, and of'Pouel, 

 our friends across tlin Channel suffer from no lack of honie-made- 

 text-books. And ou this they are distinctly to be congratulated. 



