ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 729 



is well illustrated in the incipiently dimorphic reproductive elements of 

 Volvox and the like ; (c) that male tissues, like those of an anther, exhibit 

 signs of predominant katabolism ; (d) that the female organs of Chara or 

 Nitella correspond in position to the vegetative anabolic internodal cells, and 

 the male organs to the smaller, dividing nodal cells ; (e) that over a wide 

 area the sum total of female characteristics — more vegetative, nutritive, con- 

 servative, &c. — are interpretable as anabolic, and that the average male 

 characteristics — smaller size, more active habit, higher temperature, shorter 

 life, &c. — are similarly the expression of a predominant katabolic diathesis; 

 and (/) that in the conditions affecting the determination of sex, influences 

 inducing katabolism tend to result in production of males, as those favour- 

 ing anabolism similarly go to increase the probability of females. 



And then deductively, Mr. Geddes proceeds to apply this notion of 

 anabolic " femaleness " and katabolic " maleness " to the reproductive 

 elements in their various forms and phenomena, to the processes of matura- 

 tion in oogenesis and spermatogenesis, to the physiology of fertilization, 

 to the tissues, organs, forms, and habits of the two sexes. 



(4) In regard to heredity, the author chiefly emphasizes the now familiar 

 notion of the direct continuity between the rudimentary reproductive organs 

 of the embryo and the parent ovum. The protoplasmic continuity is in 

 itself a partial explanation of the continuity in history. For " if the repro- 

 ductive elements start with a specific protoplasm continuous with that of the 

 combined mother ovum and fertilizing sperm — that is, with a concentrated 

 accumulation of characteristic anastates and katastates, the simple fact that 

 the j)roducts of protoplasmic change must be fixed, definite, and continuous, 

 as in all chemical processes, gives us at once a protoplasmic basis from 

 which to explain the constant and necessary symmetry of segmentation and 

 development." While, if superficial acquired characters be indeed in- 

 herited, " it must not be forgotten that all the organs do to a certain extent 

 share mutually in nutriment and waste products, and that thus, besides the 

 characteristic specific protoplasm acquired through direct continuity, both 

 germinal cells and developing embryo may accumulate a proportion of 

 characteristic anastates and katastates, acquired, as it were, pangenetically " 

 from the organs of the body. 



(5) The ingenious and suggestive paper closes with an application of the 

 above conceptions to the genealogical tree as a whole. In this the author 

 seeks to show how we are to " look forward to the solution of the problem of 

 aetiology in deeper terms than those of ' natural selection ' alone, as illus- 

 trations, namely, of a continuous rhythm of anabolic and katabolic change." 



History and Theory of Spermatogenesis.* — Messrs. P. Geddes and 

 J. Arthur Thomson have given (1) an historical account of the progress of 

 research in regard to the process of spermatogenesis, and have sought (2) to 

 collate in tabular form the all too-confusing nomenclature of the subject, for 

 which a symbolic notation is suggested. (3) After noting the various 

 homologies between oogenesis and spermatogenesis, the authors seek to unify 

 and rationalize the various modes of spermatogenesis described by different 

 authorities, by comparing them in detail with the various forms of segmen- 

 tation. This suggestion has also been made, though not followed up, by 

 Herrmann (1881), and has been hinted at in the nomenclature of Balfour 

 and others. The aim of the paper is to suggest that the multitudinous de- 

 tails of spermatogenesis can be morphologically rationalized by collating 

 them with the details of ovum segmentation. A bibliography and explana- 

 tory plate are added. 



* Proc. R. Soc. Edin,, 1886, pp. 803-23 (1 pL). 



