842 



SCIENCE. 



[N. S. Vol. IV. No. 101. 



the chemical type of the non-medullated nerves, 

 *. e,, of the axis cylinder." 



3. Composition of the Sperm-Heads. — The an- 

 alysis of the sperm-heads led to the surprising 

 result that it is practically possible to express 

 their constitution in a chemical formula, i. e., 

 that they are almost exclusively composed of 

 one chemical substance. This substance is 

 protamin nucleate, 



10(C,oH,,N^p,„2P,0„ C,«H,3N30,) 

 nucleic acid. protamin. 



free nucleic acid. 

 For this research the heads were first extracted 

 with ether-alcohol to remove the last traces of 

 lecithin. The substances thus obtained were 

 generally soaps, and amounted to only 0.74.- 

 2.56 fc. The lecithin of the spermatozoon is thus 

 shown to be confined entirely to the tail. The 

 poverty of the head in ether extractive is in 

 striking contrast to the richness of the tails in 

 such stuflTs. The residue of the sperm-heads 

 consists almost wholly of a mixture of the 

 nucleic acid and basic protamin salts of nucleic 

 acid. 



The protamin, a simple albuminous body also 

 isolated by Kossel from Sturgeon sperm, was 

 isolated by treating the sperm with 0.25- 

 0.50^ HCl. The protamin passes into solution, 

 the nucleic acid remains behind. There was 

 thus obtained 19.78^ of the sperm-heads as 

 protamin. The hydrochloric acid extract also 

 contained some calcium, iron, and calcium 

 phosphates amounting to 2.94^. 



The residue, after extraction of the protamin, 

 consisted in large part of nucleic acid, a sub- 

 stance characteristic of all chromatins thus far 

 examined. This constitutes, according to the 

 phosphorus determination, about 60.50^ of the 

 sperm-head. The greater part of this nucleic 

 acid is readily soluble in dilute sodium hydrate. 

 There was thus actually isolated from the heads 

 95 fo of the total nucleic acid calculated to be 

 present from the phosphorus content. It is cer- 

 tain from this determination that the total 

 amount of phosphorus in sperm free from 

 lecithin, except the trace occurring as phos- 

 phates, is contained in the nucleic acid. 



After extracting the protamin and nucleic 

 acid a small residue of the heads remained un- 



dissolved. This proved to be a compound of 

 nucleic acid and protamin which had been 

 slightly altered by the action of the extracting 

 acid used, and so rendered less soluble. 



From these analyses the composition of the 

 salmon sperm is as follows : In sperm freed 

 from lecithin and fat 87 fo of the substance lies 

 in the head, and 13 ^ in the tail. Of the orig- 

 inal unextracted sperm (containing lecithin) 76 fo 

 lies in the head and 24: fo in the tail. The tails 

 consist of 4:1.9 fo albumen, 31.83^ lecithin, and 

 26.27% fats and cholesterin. The heads con- 

 sist of 35.56% protamin, and 60.50% nucleic 

 acid, or 96.06% of neutral protamin nucleate. 

 Of the other 4%, 2.5% were insolated as gyp- 

 sum and calcium. The other 1% probably con- 

 sists of albumen. 



' ' The result that the fat-free heads contain 

 96 % of protamin nucleate is astonishing. Since 

 this salt is not an organized structure (Gebilde) 

 it is questionable whether the heads, on the 

 whole, contain any such. That the albuminous 

 matter out of which such a structure must be 

 compounded should be separated with the tails 

 on the isolation of the heads is not to be con- 

 sidered, because the heads, after the isolation 

 of the tails, on microscopical examination have 

 the same appearance as before. Treatment 

 with eosin, after good isolation, shows no trace 

 of tail, middle piece, or other albuminous sub- 

 stance remaining behind, while the inner space 

 may by the respective reagents be as beautifully 

 differentiated as before. It (the inner space) 

 has certainly a different nature from the hull, 

 although both consist of the same substance. 

 This difference rests apparently on the fact that 

 nucleic acid and protamin are not uniformly 

 distributed in the heads as a neutral salt, but 

 in such manner that the basic protamin salt of 

 nucleic acid occurs on the surface, and the acid 

 protamin salt in the interior. This is indicated 

 also by the fact, above mentioned, that after 

 treating the heads with hydrochloric acid the 

 nuclear colors are then also taken by the hull. 

 That the hull has an alkaline reaction is proved 

 by their blue coloration in decolorized cyanin 

 solution, while the inner space remains uncol- 

 ored, ' ' 



"If the sperm, nevertheless, contains a 

 special living structure (Gebilde) or a ferment- 



