' 250 The Philippine Journal of Science ms 



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 



