ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 727 



i3. Collecting', Mounting- and Examining Objects, &c. 



Collecting, Cultivating, and Displaying Microscopic Aquatic 

 Life.* — Mr. J. Levick, in Ms presidential address to the Birmingham 

 Natural History and Microscopical Society, recommends for collecting, 

 " a ring net, made of fine French canvas — a material used by ladies, 

 I am told, for the purpose of wool-work — a still finer net of muslin, 

 which will slip over it easily, making the one screwed ring do for 

 both, and being of great use when the specimens sought are too small 

 for the coarser net. A cutting hook, also, to screw to the stick ; a 

 small grapnel or four-pronged hook made of soft copper wire, about as 

 thick as a straw (or No. 9 B.W.G.) cast together by means of lead or 

 soft solder), with a few inches of brass chain attached, weighing about 

 18 ounces altogether. Then a plaited flaxen or cotton line, which 

 will not gnarl when wet, of 50 or 60 yards in length, and sufficiently 

 strong to stand a considerable pull, enough even to straighten the 

 soft hook, and so to set it free should it meet with wood or any hard 

 substance in the water which renders it fast. 



A little practice with this apparatus will enable one with a fairly 

 strong arm to throw, or rather sling, it out and gather aquatic plants 

 from a large area, 50 or 60 yards even from any favourable spot for 

 "paying" out the line, whei'e it will meet with no obstacles when 

 running out. 



How much importance I attach to the use of proper apparatus 

 may be gathered from the fact that I attribute the non-discovery of 

 Leptodora before 1879, not to its non-existence in our locality, but to 

 the want of a suitable net properly used, these creatures escaping 

 through a net too rough, and being unnoticeable, owing to their 

 extreme delicacy on the one hand, and the quantity of alga they are 

 usually taken with on the other, when a net too fine in the mesh is 

 used. 



It is quite true that the first one I obtained fiom Olton Eeservoir 

 was taken by dipping an inverted bottle to a considerable depth, and 

 then by a quick turn allowing the water to rush in ; but I have often 

 repeated the experiment where these creatures are fairly abundant, 

 and have usually failed to capture a single individual, when a few 

 sweeps with a suitable net would make a good gathering." 



Mr. Levick, in dealing with the question of choice of localities, 

 refers to "that elysium of microscopic life, the reservoir at Barnt 

 Green, which, until a large area had been scoured by means of the 

 before-mentioned hook and line, had been considered barren of any- 

 thing of special interest. It is certain that, when the bottle only was 

 dipped in near the side, nothing of more than ordinary character was 

 found ; and when the hook was sent flying through the air, and a 

 good bundle of weeds (Polygonum amphibium, I believe), was brought 

 to shore from a distance of 30 or 40 yards and carefully examined, 

 living treasures were found in perplexing abundance. I need scarcely 



* Keport and Trans. Birmingham Nat. Hist, and Micr. Soc. for 1882, pp. iii.- 



XXV. 



