The germ-cells. 6(39 



and the evil feature of a novel discovery, that it opens new fields 

 and raises new problems. The present writing does not exhaust the 

 subject; although it may modestly claim to have thrown more light 

 on the early history of the germ-cells of Elasmobrauchs than any 

 previous investigation. 



I confess, that to me the importance of making out the degener- 

 ation of all the vagrant germ-cells appears very slight and unsub- 

 stantial, as compared with the overwhelming gravity of the incontestible 

 discovery of a large percentage (28 to 30) of primary germ-cells in 

 abnormal situations in a vertebrate animal, and not in one but in nearly 

 every individual under a certain age. Its bearings on pathology, on 

 Cohnheim's theory, and on the brilliant discoveries of Wilms relat- 

 ing to dermoid cysts, must be apparent. The mere occurrence of such 

 vagrant germ-cells in all sorts of situations is sufficient. 



Whether or not they all usually ultimately degenerate does not 

 affect the application and import of the discovery. Even had the degene- 

 ration of scores of them been witnessed, instead of a mere tithe, the 

 writer would still have felt bound to point out, that some of them would 

 appear to be in positions as favourable for further persistence as in 

 the germinal nidus itself. As examples those frequently found on the 

 subintestinal vein may be cited. 



Doubtless, however, the pathologists will feel satisfied with the 

 discovery, that in a vertebrate animal 28 to 30 per cent of the primary 

 germ-cells may at certain periods be in impossible situations. They will 

 not wish to assume, that as a general rule even one per cent of 

 these persist. They will only demand the occasional presence in 

 later " embryonic life, youth, adult, or old age, of one or two such 

 vagrant primary germ-cells, in order to account fully for their finds. 



XIL Dermoid Cysts and Teratoinata. 



This is the title of an important research by Max Wilms 

 of the University of Leipzig. Not being a pathologist, the writer has 

 no knowledge of the effect produced in pathological circles by the 

 publication of this original investigation. It cannot be at all widely 

 known to vertebrate embryologists. Had it been published in an em- 

 bryological journal as a developmental treatise, it would probably 

 have created an immense sensation. 



The author ^) seeks to prove, and to my mind with complete suc- 



1) Max Wilms, Ueber die Dermoidcysten und Teratome etc., in: 



44* 



