SOLID PARTS OF ANIMALS. 



Mulder considers the substances thus obtained as constituting 

 the principles of which the silk is composed. 



1. The substance extracted by boiling water, and remaining 

 after the residue of the decoction had been treated with alcohol 

 and ether, was heavier than water, friable, and destitute of taste 

 and smell. It did not totally dissolve in water. The solution 

 w as thick and opal, and adhered to the fingers ; but it did not 

 gelatinize on cooling. Both silks yielded to boiling water two 

 different substances, one of which was insoluble in boiling water, 

 and could be separated by the filter, the other forming a thick 

 adhesive solution. The first of these substances Mulder consi- 

 ders as albumen, the second as gelatin. 



2. The flocks which were deposited from the alcoholic solution 

 when it cooled, he distinguishes by the name of cerin. 



3. The substance which remains when the alcoholic solution, 

 freed from the bulky flocks, is evaporated to dryness, consists of 

 a fatty matter and a resinous body, and besides these two in the 

 residue from the yellow silk, there was a quantity of colouring 

 matter. 



4. What the ether dissolved was also a mixture of fatty mat- 

 ter and resin. 



5. The substance dissolved from the silk by concentrated ace- 

 tic acid possessed the characters of that obtained by water, and 

 which he had already distinguished by the name of albumen. 



6. The substance remaining undissolved after the silk had been 

 subjected to the action of all these reagents, Mulder considered 

 a&Jibrin. 



The following table shows the results obtained by these ana- 

 lyses : 



Yellow Silk. 



Fibrin, ; ." . 53-37 

 Gelatin, . 20-66 



Albumen, . 24-43 



Cerin, . . 1-39 



Colouring matter, 0-05 



Fatty matter and resin, 0-10 



100-00 100-00 



1. The properties of the fibrin from silk and its constitution, 

 according to Mulder's determination, have been given in a pre- 



