October 14, 1898.] 



SCIENCE. 



517 



investigation in other groups of animals will 

 have the same result. Here I shall add another 

 instance. Dr. Murray (L c, p. 134) gives a list 

 of bipolar species and genera of fishes (after 

 Giinther). Now I took the trouble and tried 

 to verify this list, using the recent publications 

 of Jordan and Evermann* and of Goode and 

 Beanf , but I was very much astonished to find 

 that this list is of no value at all. After having 

 found out that of eleven bipolar species of this 

 list at least five are really not bipolar, and that 

 of twenty-eight bipolar genera at least ^ue are 

 to be dropped, and that seven more are very 

 doubtful, I did not think it worth while to 

 examine the whole list, since it is evident by 

 these facts that it is utterly devoid of scientific 

 value. 



In order to avoid any misunderstanding, I 

 wish it to be understood that I do not deny the 

 possibility of ' bipolarity,' and, indeed, I have 

 myself established at least one instance of true 

 bipolarity of a genus (Crangon), and I have 

 given an explanation of it. But I protest most 

 emphatically against the view that bipolarity 

 is a striking character of the marine polar 

 faunas, and I also protest against the introduc- 

 tion of doubtful or poorly established facts or 

 of simply incorrect statements or opinions (cf. 

 Lithodidss) in support of this ' bipolarity ' of 

 species or groups. 



Arnold E. Oetmann. 



Peinckton TJniveesity, September, 1898. 



SCIENTIFIC LITERATURE. 

 Die Zelle und die Gewehe. Grundziige der 

 allgemeine Anatomic und Physiologic. Os- 

 CAE Heetwig. Jena, Gustav Fischer. 1898. 

 Zweites Buch. Allgemeine Anatomie und Physi- 

 ologie der Oewehe. Pp. viii + 314. 89 figs. 

 Preis, 7 Mark. 



The first part of the work, of which this 

 forms the second and concluding volume, ap- 

 peared in 1892. Its appearance, as the author 

 tells us in the preface, was due to three reasons: 

 first, to impart to a wider circle of readers the 

 views set forth in his university lectures; second, 



*The Fishes of North and Middle America, Bull. 

 U. S. Nat. Mas., 47, 1896. 



t Oceanic Ichthyology, Mem. Mus. Comp. Zool., 

 V. 22, 1896. 



the desire to give to his own investigations, 

 scattered in various periodicals and separate 

 publications, a more comprehensive setting; 

 and third, to crown his ' Lehrbuch der Ent- 

 wicklungsgeschichte des Menschen und der 

 Wirbelthiere ' with more theoretical views, 

 which could not suitably be included there. 

 "But the second part of the book, which in- 

 cludes the subject of the tissues, and which 

 will be about the same size as the first part, 

 will be in a more special sense a completion of 

 the ' Embryology.' For in it, in addition to the 

 description of the tissues, special emphasis will 

 be laid on their origin or histogenesis, and on 

 the physiological causes of tissue-differentia- 

 tion." The entire work is thus the result of the 

 life-long observations and reflections of one of 

 the most active and successful of modern biolo- 

 gists. It is the product of a true process of 

 growth, and, probably, a final product; for 

 those who have carefully followed the author's 

 writings of the last six years will not find in 

 this volume much not outlined before. 



Perhaps the chief significance of the present 

 volume is that it is the first thorough and con- 

 sistent exposition of Lamarckian principles, as 

 seen in the light of recent embryological work. 

 The leading idea of the entire exposition is the 

 the author's theory of development, which he 

 names the theory of Biogenesis. The three 

 foundation stones of this theory are stated in 

 the twentieth chapter to be: (1) Lamarckism, 

 i. e., 'to use Nageli's expression, the theory of 

 the specific and direct action ' of the environ- 

 ment ; (2) ' the doctrine of the inheritance of 

 acquired characters, or their transmissibility 

 through the germ-cells to the offspring;' (3) 

 ' the doctrine of the continuity of the process 

 of development, and the principle of progres- 

 sion, that is to say, that development ' (both 

 ontogenetic and phylogenetic) 'i^rogresses stead- 

 ily in a definite direction.' 



The first seven chapters are preliminary, 

 dealing with 'the Stages of Individuality,' 

 ' Specific (Artgleiche), symbiotic and parasitic 

 cell-union,' 'On the Methods of Interdepend- 

 ence of the cells of Organisms,' 'The Law of 

 Causation in its Application to the Organism,' 

 ' On the Causes Separating Cell- aggregates into 

 Tissues and Organs,' and the 'Theory of 



