274 RAIN-WASH. 



had a similar origin* to our Derbyshire rain-wash ; the red cave-earth of 

 limestone caverns (Kent's Cave for example) is a similar residue. All 

 the soil of our fields, of com'se, is in large measure due to the disintegrating 

 and chemical action of rain, but I should prefer to retain the term rain- 

 wash, geologically, for any residuum which is wholly due to its action. I 

 should be glad to hear from any correspondents whether they have 

 observed any instances of deposits similar to that noted above, and under 

 what conditions. I believe there are some thick clay beds at the foot of 

 the Weaver Hills, which have been mistaken for boulder clay, but are 

 really nothing but rain-wash, but these I have not yet examined ; will 

 anyone describe them for us ? 



W. J. H. 



* Might not the well-known bed of red clay in Tideswell Dale have had a similar 

 origin. 



THE PROPAGATION OF ME LICE RT A RINGS NS IN 

 AN AQUARIUM. 



No one I feel sure can look at Melicerta ringens under the microscope 

 without being moved by feelings of the greatest admiration, and at the 

 same time of regret that such Ijeautiful creatxires are to be found only in 

 few places. I confess such were my own feehngs after having examined 

 some fine specimens kindly sent to me by Mr. Thomas Bolton, of Bir- 

 mingham, in February last ; and I thought if Melicerta ringois could be 

 successfully maintained in an aquarium that it would afford an excellent 

 opportunity for the study of the life histoiy of those beautiful creatures. 

 I therefore determined to make the attempt, and am pleased to say my 

 success has been greater than I anticipated. I did not succeed with my 

 first trial, but in the following month Mr. Bolton sent me some 

 remarkably fine specimens. With these I set to work again, and in 

 proof of iny success, there is now in a beaker before me two pieces of 

 Myriophyllum, one four inches long, to which are attached 200 specimens, 

 and on another piece, three inches long, there are 150 specimens of 

 Melicerta ringens. Indeed, I am sure there are altogether over 1,000 

 specimens in my aquarium. 



Perhaps a description of my aiTangements would be acceptable to 

 many who may desire to have this interesting object always at hand. I 

 feel certain these arrangements will prove as successful in the hands of 

 others as they have in mine, and a knowledge of them will, perhaps, 

 induce many to enter into the study of Melicerta ringens, as suggested by 

 Mr. F. A. BedweU in his admirable notes on this subject in the last 

 number of the " Midland Naturalist." I now proceed to describe the 

 plan I have followed, and to point out the conditions which my 

 experience indicates are especially favourable to the propagation of this 

 interesting Rotifer. 



The room in which my aquaria are kept is lighted by one window 

 which looks due east ; against the south side of the room there is a side- 

 board, the nearest end of which is three feet from the window. On the 

 sideboard are two aquaria, one holding 1^ gallons and the other four. 



