A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



' ' To the solid ground 

 Of Nature trusts the mind which builds for aye.'''' — Wordsworth. 



THURSDAY, MAY 5, li 



SCIENTIFIC WORTHIES. 

 XXXI. — Albert von Kolliker. 



ALBERT VON KOLLIKER was born at Zurich on 

 July 6, 1817 ; he therefore is the eldest of the 

 illustrious teachers who have brought down to the 

 present day the tradition of that active spirit of bio- 

 logical inquiry which had its most complete expression, 

 during the first part of the century, in the life and work 

 of Johannes Muller. 



After visiting several universities, and so hearing the 

 lectures of many eminent biologists (among whom 

 Johannes Miiller himself may be specially mentioned), 

 Kollifeer took the degree of M.D. in Heidelberg in 1842 ; 

 and in 1843 he commenced his teaching career as 

 Prosector to Henle in Ziirich. In 1846 he became 

 Professor extraordinarius in Ziirich, and in the autumn 

 of 1847 he was called to Wiirzburg as Professor of 

 Human Anatomy. This chair he has continuously occu- 

 pied ever since. The remarkable Festschrift, recently 

 published in his honour, contains a long list of names of 

 men who are proud to call themselves his pupils ; and the 

 scientific position which so many of these men have won 

 is evidence of the way in which he has fulfilled the highest 

 function of a teacher, imparting to his hearers not only 

 a great store of knowledge, but a just perception of the 

 point where knowledge ends, and something of his own 

 •determination and energy in the acquisition of new 

 scientific truth. 



It is impossible to give anything like a detailed 

 account of Prof, von Kdlliker's scientific work, the results 

 of which are embodied in some couple of hundred 

 memoirs (written with apparently equal facility in any 

 one of four languages) and in a series of text-books. All 

 that can be attempted is an outline of its most important 

 features. 



The publication, in 1838, of Schwann's great work 

 drew attention to a number of problems ; and Kolliker 

 was one of the first to realise that the complete justi- 

 fication of the cell-theory must be accomplished by a 

 NO. 1488, VOL. 58J 



study of the whole history of animal tissues, from the 

 fertilised ^%!g onwards. The first results of this con- 

 viction are seen in his monograph of the development 

 of Cephalopods (1844), and in a series of papers on the 

 development of Amphibia (1846-1847). These memoirs 

 are of great importance in the history of embryology, 

 because they definitely bring the phenomena of the seg- 

 mentation of fertilised ova into the category of normal 

 cell divisions, and lay the foundation of the modern 

 doctrine that an ovum is to be regarded as a single cell 

 Speaking in i860 of his work on the Cephalopoda, Prof, 

 von Kolliker points out, with justifiable pride, that he 

 had already in 1844 asserted 



" Dass in der ganze Reihe der Entwicklung der 

 thierischen Gevvebe, ebensowie bei den Pflanzen, keine 

 Zellenbildung ausserhalb der schon vorhandenen sich 

 finde, vielmehr alle Erscheinungen als die ununter- 

 brochene Folge von Veranderungen urspriinglich gleich- 

 bedeutender und alle von Einem ersten abstammender 

 Elementarorgane aufzufassen seien " — 

 the process of derivation being always a cell-division 

 comparable with the division of cells in a later embryo, 

 or in the adult body (cf. Ent-wicklungsgeschichie^ ed. 

 1861). But besides this important general proposition, 

 the memoir contains a detailed account of Cephalopod 

 development, so far as it could be studied by the methods 

 available at the time, which is of great and permanent 

 value to students of molluscan embryology. The papers 

 on the development of Amphibia describe in outline the 

 process by which the cells of cartilage and blood, the 

 walls of blood-vessels and the elements of embryonic 

 muscle are derived from blastomeres, and therefore have 

 an important bearing on the fundamental problems of 

 histogenesis. 



A second series of early papers (i 841-1847) was of 

 great assistance, although in a different way, to the study 

 of animal development. The acceptance of Caspar 

 Wolffs doctrine of epigenesis, while it led to a right 

 understanding of the structure of the ovum, was 

 accompanied for a time by a curious belief concerning 

 spermatozoa. After the discovery o{ these bodies in 

 Leeuwenhoek's laboratory (1677) they were held by 

 many supporters of the hypothesis of " evolution " to con- 

 tain the whole preformed germ of the future animal, 



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