STAINING, PRACTICAL AND THEORETICAL 



Notes: 



Johansen (1940) states that he considers Haupt's fluid by far 

 the best adhesive yet devised for attaching sections to shdes, and 

 that he finds it may be used for affixing unicelkilar and many 

 colonial algae. He also directs that a drop of the adhesive should 

 be smeared evenly on the slide to leave a barely perceptible 

 layer. A few drops of 3 to 4% formalin are then added and the 

 section floated on this, on a warm-plate at 40 to 43° C. (for sections 

 embedded in paraffin wax melting point 58 to 60° C.) until the 

 section has flattened out. The slide is then allowed to cool, when 

 the excess formalin is drained oflr, and the section positioned as 

 desired. If the specimen, fixed to the still wet slide, is placed in 

 an oven together with a dish of full-strength formalin, the form- 

 aldehyde fumes will reinforce coagulation of the gelatine. 



Reference: Haupt, A. W. (1930). 



KOLLOFAST 



An excellent fluid, superior to Kaiserling, for preserving either 

 anatomical or botanical museum specimens permanently in their 

 natural colours: the preservative is equally satisfactory for both 

 normal and pathological specimens. Brightly coloured specimens 

 such as lizards and snakes, and leaves and fruits are preserved 

 permanently in Kollofast, showing their natural colours and with 

 the areas of infection, if any, clearly differentiated as in life. This 

 technique is a two solution method: specimens are fixed in 

 solution A, the time of fixation varying according to the size and 

 nature of the specimen. After fixation and washing in water, the 

 specimens are preserved permanently in solution B. 



LAKTOSEAL 



(Edward Gurr) 



A quick-drying, transparent, colourless cement for sealing 

 lactophenol, glycerine and other aqueous mounts. 



530 



