MisceUaneous. 151 



has attained its greatest exuberance, namely, when the summer 

 months are past and the hght is beginning to decrease in its in- 

 tensity and the days to shorten. So exactly, indeed, are the ener- 

 gies of the plants regulated by the amount of light to which they 

 are exposed, that a constant arrangement, such as that here des- 

 cribed, affords an excellent indication of the variation of the seasons 

 in different years, or might even be made a rough measure of the 

 total amount of light from month to month. 



But while the demand for carbonic acid on the part of the plant 

 varies in this manner with the seasons, the amount of that gas pro- 

 duced by the respiration of the fish is very nearly the same all 

 through the year. Whence, then, does the plant oijtain that addi- 

 tional quantity of food which its stimulated energies require during 

 the spring and early summer months, and which its rapid and 

 luxurious growth show to be readily supplied ? After what has 

 been stated, I think the soui'ce must be apparent to every one : it 

 is the carbonic acid which has been gradually accumulated, and 

 rendered innocuous to animal life from its being held in combination 

 with carbonate of lime, in so marvellous a manner during the 

 winter months. Stored up, yet held in feeble combination, a com- 

 bination so weak that the vital forces of the fresh-growing vegetation 

 can easily overcome it, and resolve once more into carbonate of lime, 

 carbon, and oxygen the bicarbonate of lime contained in the water *. 



Thus beautifully are the necessary irregularities in the purifying 

 action of the plant compensated and provided for, that the balance 

 of existence between the animal and vegetable organisms be not 

 disturbed or overthrown, and thus additional proof is furnished, if 

 such were needed, of the wisdom of that creative power that has 

 ordered all things to work together for good, and by endowing certain 

 bodies with such seemingly minute and insignificant affinities, main- 

 tains the glorious harmony of the whole. 



MISCELLANEOUS. 



Errata in Localities of Indian and Burmese Squirrels. Necessitij of 

 defining more exactly what is understood by India. 



To the Editors of the Annals and Magazine of Natural History. 



Gentlemen, — In Dr. Gray's very useful Synopsis of the Asiatic 

 Squirrels in the Collection of the British Museum, published in the 

 October number of the ' Annals,' some of the localities are incorrect. 

 I venture to point out two or three such cases. I do not suppose 

 that Dr. Gray is responsible for their accuracy, as he has doubtless 

 taken them from the specimens in the British Museum ; but, in any 



* The rapid growth of submerged vegetation in rivers and waters containing 

 a considerable amount of carbonate of lime must have been observed by all 

 interested in the subject, in some cases obliging the cleansing of such streams 

 three or four times dialing the year. 



