1895.] MICROSCOPICAL JOURNAL. 35 



ical brass screen (o) of woven-wire, with meshes of l-16t]i 

 inch. This, being mounted with its point forward, read- 

 ily cuts through beds of weeds or any obstructions 

 amidst which the net could possibly be used in any way, 

 allowing free entrance to the water and micro-organisms 

 (and, unfortunately, to fine sand or soft mud), but ex- 

 cluding weeds, stones or coarse rubbish of any kind. The 

 net (a) is made of fine cheese or bolting cloth or some mus- 

 lin or lawn of suitable texture, and is strengthened by 

 being made of double thickness for a few inches at each 

 end (g, r) ; and as water passes in at "o" and out at 

 ''q, a, r," under pressure of dragging the net forward 

 through the water, the contained organisms naturally ac- 

 cumulate within, at the rear end, whence, after remov- 

 ing a screw cap {t) from a 1-inch tube (s) inserted in that 

 end, they are to be washed out into a. bottle. This net 

 was suitable for microscopic forms, from Cyclops to dia- 

 toms ; for large insects, fish spawn, etc., a coarser screen 

 and more open cloth would be used, according to what 

 one wished to fish for ; while a coarser screen and fine 

 lawn would take everything, including much rubbish. 



As I have seen this net used, a cylinder of sheet cop- 

 per, not unlike a bit of stove pipe four inches in diame- 

 ter and of twice that length, connects the conical screen 

 with the mouth of the net. This cylinder may possi- 

 bly make the net less liable to entanglement or tearing 

 when thrown out from shore among thickets of coarse 

 weeds, to be drawn back again by its tow-line, as is 

 sometimes done in the absence of a boat. But for the 

 sake of portability, and also hoping to secure a more 

 manageable implement, one was made, as shown in the 

 Fig., without the cylinder, the net (a) being fastened to 

 a hoop (p) of sheet copper, 4 in. in diameter and f tlis in. 

 long, soldered to the base of the wire screen-cone (o) ; 

 the net-edge of the hoop being turned up over a wire, as 

 the edges of tinware are often protected, which stiffens 

 the hoop and makes it impossible for the net to slip off 



