24 



The Naturalist. 



50,000 in reserve, the rest in use. The water is always changing 

 position ; it is pumped from the spare tank into those which contain 

 fish, and from which it returns to its original receptacle, " so that a 

 constant and perfect circulation is maintained. This process itself 

 constantly exposes fresh surfaces of water to be oxygenated by the 

 surrounding atmosphere, although its still more perfect oxygenisa- 

 tion is secured by the force of the streams delivered into the stock 

 tank." The water, which was all procured from Blackpool, will 

 need no renewing beyond that necessary on account of leakage or 

 evaporation. Those tanks whose inhabitants need an artificial tide, 

 are also supplied by means of taps with high and low water. Another 

 feature in the Manchester Aquarium is the fresh water department, 

 which is supplied on the same principle and is a great success. 



(To he continued.) 





Height 



of 

 gauge 

 above 



sea 

 level. 



Rain- 



No. 



of 



Total Fall. 

 TO Date. 



Date of 

 heaviest 

 Fall. 



Amount 

 of 



heaviest 

 falL 



1 







Days 



1877. 



1876. 





Ft. 



350 





In. 

 2-73 



14 



21-61 



*16 99 



14th 



0-70 



(J. W. Eobson.) 









Wakefield (F.HiU.)... 



120 





2-93 



19 



18-99 





14th 



0-88 



Leeds ...(H. Crowther.) ... 



183 





3-55 



16 



18-48 





15th 



0-89 



Bamsley (T. Lister.) . . . 



350 





m 















853 





O M 













Wentworth Castle (Do.) 



600 

















Goole... (H. F. Parsons.) ... 



25 





1-97 



15 



13-42 



12-01 



14th 



0.65 



* This is the average to July for 11 years, 1866-76. 



Mecyna polygonalis at Deal. — Mr. W. H. Tugwell, of Greenwich, 

 writes me that he has taken a beautiful specimen of this species at Deal. 

 This I believe is only the second recorded occurrence in Britain, the last 

 having been taken at Bury St. Edmunds in 1868. — Geo. T. Porritt, 

 Huddersfield, August, 1877. 



