372 On Parasites, Animal and Vegetable^ 



throughout its most minute details, the metamorphoses of the 

 greasy tissue of the insect into the radicle or thallus of the 

 new cryptogamous plant, the Botrytis bassiana^ which assured- 

 ly is the alone cause of the malady. The memoirs of M. Au- 

 douin have been honourably mentioned in a report of the Aca- 

 demy, drawn by M. Dutrochet, and his conclusions approved 

 of. M. Audouin, a few months ago, received a letter from his 

 friend M. Eudes Deslonchamps, Professor of Zoology at Caen, 

 which he read to the French Academy, and in which an ac- 

 count is given of the growth of a cryptogamous plant in the 

 air-cells of a duck, which rapidly killed it. The particulars of 

 this interesting case we shall now supply. 



In the month of December 1839, Dr Blot, whose residence 

 is not far from the sea, was presented with an eider-duck which 

 had recently been captured in a trap ; and whose plumage shewed 

 it to be either a female or a young male. It was very gentle, and 

 was put into the poultry-yard, where it was soon at home with 

 its new companions. It was almost always in the water ; and 

 when its pond was frozen over, the ice was broken for its ac- 

 commodation. In the spring it moulted, and then proved to 

 be a young male. 



Three weeks or a month before its death it appeared less 

 active than usual ; it ate less, and resorted but seldom to teh 

 pond. Presently it was observed frequently to stretch its 

 neck and extend its wings as if it had difficulty in breathing, 

 and speedily this difficulty became urgent, the poor creature 

 supporting its wings on the ground, and making great efforts 

 to force the air into its chest. When it was lifted up, the 

 strong muscular exertions it made for breath were distinctly 

 felt. At the same time it was perceived that, from being very 

 fat, it was gradually becoming exceedingly lean. On the 2d 

 of July 1840, Dr Blot missed the eider-duck from the poultry- 

 yard, and on going in search found it in its nest, whither it 

 retired every night, and where it was still warm. The same 

 day it was sent to M. Deslonchamps, who, on the moment, un- 

 dertook its dissection. His purpose was to examine the heart 

 and great vessels ; and he took every precaution that no part 

 should be injured. The air-cells were immediately opened 

 freely, and his surprise was great on finding them lined with 



