302 THE PHYSIOLOGY OF REPRODUCTION 



as Bocariiis^ believes, since other secretions and tissue extracts which 

 do not contain spermine give the same reaction. 



Joestens^ considers that the crystals obtained in Florence's 

 reaction are perhaps merely iodine without any choline. Warmed 

 with a watery solution of gold tribromide semen gives on rapid coohng 

 characteristic yellow crystals which are stated to be due to the 

 presence of both choline and spermine and which show accordingly 

 different forms.^ 



Another reaction for semen, which is much more specific, has 

 been discovered by Barberio. By the addition of picric acid, fine 

 rhombic or needle-shaped crystals are formed. It is doubtful which 

 substance is responsible for this reaction. The observations of 

 Littlejohn and Pirie* show that the substance which forms the 

 crystalline picrate is secreted by the prostate and by Cowper's glands, 

 and,, further, that this substance appears to be specific for human 

 semen, since a negative result is obtained with the semen of monkeys, 

 rabbits, and rats. 



The Chemistry of the Spermatozoon ^ 

 Owing to the brilliant work of Miescher,^ which has been con- 

 tinued by Kossel '' and his pupils, our knowledge of the chemistry 

 of the spermatozoon is more complete than that of any other cell. 



Thanks to the intelligent generosity of the head of a large fishery 

 concern in Btle, Miescher obtained a liberal supply of the milt of the 

 salmon, the sexual organs of which develop during the passage up 

 the Rhine. By controlhng his mechanical manipulations by means 

 of histological observations Miescher was able to investigate separately 

 the different morphological elements of the spermatozoa. The tails of 

 the spermatozoa are very rich in phosphorised fats, and contain besides 

 a typical protein, cholesterin, and fat, in the following proportions : — 



Per Cent. 

 Proteins 41-90 



Phosphorised fats 31 "83 



Cholesterin, fats 26'27 



^ Bocarius, " Zur Kenntniss der Substanz welche die Bildung von Florence- 

 schen Krystallen bedingt," Zeitsch. f. physiol. Ghem., vol. xxxiv., 1902. 



^ Joestens, " Experitnentelle Untersuchungen uber die Plorence'sche 

 Beaktion," Vierteljahrschrift f. geriehtliche Medizin, vol. xlv., 1913. 



' De Dominicis, " Uber eine Spermareaktion mit Goldtribromur, " Viertel- 

 jahrsch. f. geriehtliche Medizin, vol. xliv., 1912. 



* Littlejohn and Pirie, " The Micro-Chemical Tests for Semen," Edin. Med. 

 Jour., 1908. (This paper contains references to the literature.) 



^ For a detailed account of this subject and the literature see Burrian, 

 " Chemie der Spermatozoen," I., in Ergebnkse der Physiologie, vol. iii., 1904 ; 

 and " Chemie der Spermatozoen," II., in Ergehnisse der Physiologie, vol. v., 1906. 



* Miescher, Hiatochemische und Physiologische Arbeiten. Cfesammelt und 

 Herausgegehen von Seinen Freunden, vol. ii., Leipzig, 1897. 



' Kossel, "Tiber die einfachsten EiweisskSrper," Biochemisohes Oentralblatt, 

 vol. v.. Parti., 1906-07. 



