150 VEGETABLE PAEASITES. 



which had before been proposed by others (Von Walther), with 

 much energy, and compares the mass which exudes during 

 the adhesive process and the changes in the hair itself, to the 

 processes which we observe going on in the feathers of birds 

 during their falling off and ijestoration in consequence of 

 moulting. I am sorry to say that the results he has arrived at 

 are little calculated to carry conviction fit to bribe the rational 

 practitioner, however much Herr von Studzieniski may appeal to 

 the feelings of practical men in the words of his preface, and con- 

 cluding phrase: "This book," he says, "belongs to the practitioner." 

 Medical men are not made expert by mere theories, however 

 plausible, but by results borne out by experiment, and made pro- 

 bable by exact chemical or microscopic researches, and they must 

 always look with suspicion upon a theory where the variations in 

 the action of nervous polarity play a principal part. No ex- 

 periments are to be found in the book, though it must be 

 admitted that it contains much to interest and to invite to future 

 rational researches. When Herr von Studzieniski mentions 

 further the following diseases as related to plica polonica, viz., 

 Pellagra (in which the formation of scales predominates), the 

 Asturian Hose (Lepra asturiensis, in which the formation of 

 scales prevails), both seated in the horny tissues where hair is 

 found ; and next Ichthyosis, which, according to Rosenbaum, is 

 the exudation of the blastema of the hair in a shapeless state on 

 the surface of the head, and which spares the hairless palm of the 

 hand and sole of the foot ; and further, the Cornua cutanea, or 

 cutaneous horns, which are, according to Rosenbaum, hyper- 

 trophied hair and hair germs, and lastly the Scarlievo : we can 

 but call the author's theory to some extent ingenious. It is true 

 that the latter epithet could scarcely be applied to the opinion, 

 "that even scirrhus is a disease of the moulting process." It 

 is, however, incomprehensible, that in such a work the para- 

 sitical nature of the plica is passed over without the slightest 

 notice being taken of it, or any investigation of this view. Herr 

 von Studzieniski goes even so far as not to mention at all 

 Giinzburg's name either in his text or in his literary appendix. 

 Historical interest is attached to the evidence, that the plica 

 polonica was brought to Pakutia, fifty years earlier than to 

 Poland, by the people who fled before the Mongolian Tartars, 

 and were called Koltun, a name said to be a nickname in these 

 countries to the present day. The disease did not at first appear 



