MISCELLANY. 103 



It might perhaps be imagined, that the air contained in the pneumatic organs 

 of the nerves of the corolla, would act by virtue of its elasticity to produce the 

 incurvation of sleep, and not by virtue of the chemical action of the oxygen it con- 

 tains : hence it would be inferred that the incurvation of sleep would not take 

 place in a corolla plunged in non-aeriated water, which dissolved the air contained 

 in the pneumatic organs, and which takes its place. But it is not so : experience 

 has proved to me, that the air never returns into the pneumatic organs occupied 

 by the water, in the vegetable portions which remain sub-merged. Now, that 

 does not prevent the corolla of Mirabilis from closing after two or three days, 

 when the non-aeriated water in which it had been immersed expanded is allowed 

 to aerate itself by contact with the atmospheric air. It is therefore undoubtedly 

 by the chemical action of the oxygen dissolved in the water that the fibrous 

 tissue acquires the power of incurvation which produces the dormant state. 

 Thus, in the floAver of Mirabilis, the waking and sleeping — that is the opening 

 and shutting of the corolla — result from the alternately predominant action of the 

 two organic tissues situated in the nerves of the corolla, and which curve in 

 opposite directions, e.g. :• — 1. A cellular tissue which inclines to curve outwards, 

 by impletion of fluid in excess, or by endosmose ; 2. A fibrous tissue which 

 tends to curve inwards, by oxygenation. — Annates des Sciences Naturettes. 



CHAPTER OF MISCELLANIES. 



ZOOLOGY. 



Egg of the Cuckoo (Cuculus canorus, Linn.). — How is it that the egg of 

 the Cuckoo, though large compared with those of the bird in whose nest it is 

 deposited, takes only the same time for incubation ? This is a curious subject, 

 and one on which I should be glad to have even the conjectures of others. 

 Wilson mentions a similar fact with respect to the egg of the Cow Bunting of 

 America, but does not give any solution of the cause. — B. It. Morris, Charmoutk, 

 Dorsetshire, Dec. 17, 1837. — [[Although as a general rule the largest eggs require 

 longest incubation, there are many exceptions to the law. For instance, the eggs 

 of the Goose and Duck — though differing very considerably in size — are hatched 

 in a similar period. Probably the relative thickness of the shell, or the quality 

 of the yolk, may have some influence ; but we merely throw this out, as desired 

 by our correspondent, in the way of " conjecture." — Ed. J 



Notes on Birds met with near Plymouth. — The following birds have been 

 found near Plymouth, to the mild climate of which neighbourhood the appear- 



