250 The Philippine Journal of Science i9is 
The net itself, of batiste or pearline lawn of suitable fineness, 
is conical in form, with the lower end open and just large enough 
to hold the upper end of the glass receptacle in the last centi- 
meter of its length. The upper circumference of the net is 
sewed to a muslin band about 8 cm wide. The ends of this 
band overlap, but are united only by the lower and upper edges, 
leaving a placket gap for changing the glass receptacle when 
breakage occurs after the net is completed. The upper edge 
of the muslin band is hemmed to a metal ring, either plain or 
mounted with solder on the smaller end of a tapering ferrule. 
The plain rings are provided with strings for attachment to a 
pole. The mouth of the net is closed with a piece of bobbinet 
sewed to the muslin band near the ring for the purpose of ex- 
cluding large objects. With this net it is easy to strain the 
organisms of certain dimensions from large volumes of water 
and wash them down into the receptacle where they may be 
inspected with a pocket lens. 
In place of specially prepared sedimentation tubes, homeo- 
pathic vials have been used by cutting off the bottoms and 
smoothing and flaring the cut ends to fit the net. Nets with 
small rings or rectangular frames have been made to fit in 
metal pocket boxes such as those in which some brands of 
candy and tobacco are sold. The nets require to be dried before 
being stowed in these boxes. 
Experience has shown that, in the tropics at least, the delicate 
fabrics, such as batiste, are liable to injury by gnawing insects 
unless well protected. One new net stood for several weeks 
against a wall and when used for the first time was found to 
have been eaten in several places. After repair with patches 
fixed in place with a mixture of beeswax and resin, the net was 
used, dried, and placed in a desk drawer. When required for 
use again it was found to have a fresh lot of insect holes. The 
nets in metal boxes are constantly ready for use. 
WASHING DEVICES FOR SMALL OBJECTS 
For washing chrom-acetic fixing solutions from quantities of 
Volvocaceae, amounting to several cubic centimeters in some 
cases, by a flow of distilled water, which neither compacts the 
mass of organisms nor washes any of them away, I have used 
several devices. The more satisfactory of these will now be 
described. 
A simpler form consists of a calcium chloride U tube with 
two side tubes, fitted with a cork or rubber diaphragm holding 
a filter-paper floor, and a bent glass tube connected by a short 
