52 Vaination in the colour of cocoons, tC-c. 



shock of disturbance may have led to a retention of the 

 brown iluid, though this cannot be proved. 



After these experiments were performed I received 

 information that Mr. Poulton^'' and Prof. Meldola have 

 shown that the cocoon of Eriogaster is largely made up 

 of oxalate of lime, vv^hich is deposited on the first thin 

 web of silk. There was no direct evidence as to the 

 manner in which this substance is deposited, but it was 

 believed to be voided from the intestine. This observa- 

 tion would thus to some extent give support to the 

 suggestion here made, that the colouring matter of the 

 cocoons is produced chiefly, if not altogether, from the 

 intestine. 



* In a paper read before the Physiological Societv, not yet pub- 

 lished (February, 1892). 



