t 4 2 SCIENCE PROGRESS. 



the thyminic acid which they have isolated by removing the 

 nuclein bases from thymus nucleic acid to be a paranucleic 

 acid, but this cannot be considered proved until we know 

 more about the solubilities and decomposition products of 

 paranucleic acids prepared directly from casein and similar 

 bodies. 



The nucleo-albumins in contradistinction to the nucleo- 

 proteids are apparently contained in the cell protoplasm and 

 behave as strong acids, insoluble in water but readily dis- 

 solving in weak alkali. A neutral solution of their alkaline 

 compound does not coagulate on heating and they appar- 

 ently always contain iron and less sulphur than ordinary 

 proteids. 



In a recent paper Milroy 1 has examined the bodies ob- 

 tained by precipitating acid solutions of proteids with nucleic 

 and thyminic acids. The former Altmann considered as 

 identical with the nucleins, and Milroy shows that these 

 artificial nucleins and paranucleins give many of the re- 

 actions of the true nucleins and paranucleins, e.g., their solu- 

 bilities, percentage of phosphorus and behaviour to digestive 

 ferments are the same ; this resemblance however, is not 

 sufficient to establish complete identity. 



PROTAMINE. 



Another compound of nucleic acid is with the protamine 

 bases. So far these have only been found in the nuclei of 

 the spermatozoa of fishes. The protamines are nitrogenous 

 bases, only found at present in this position, and have 

 recently been considerably studied in this connection. 



The nucleic acid in the nuclei of the salmon spermatozoa 

 appears to be present combined with a base which Miescher - 

 termed protamine, and to which he assigned the formula 

 C 9 H 2I N 5 3 . It forms about one-fourth of the total weight 

 of the dried spermatozoa heads, and was isolated from them 

 by repeated extraction with dilute hydrochloric acid (about 



1 Milroy : Ztschr. f. physiol. Chem., Bd. 22, S. 307, 1896. 



2 Miescher : Verhandl. d. naturf. Gesell. in Basel, Bd. 6, S. 138, 1874 ; 

 and Ber. d. d. chem. Ges., Bd. 7, S. 396, 1874. 



