136 



If the watch glass has been smeared with 

 glycerine it will be easy to remove the block. 



9. Cut out the specimen, arrange as desired 

 for cutting transversely, vertically, or horizontally. 

 Take care that the top and bottom edges of the 

 block are parallel. Smear these with a little 

 melted soft paraffin (made by melting a little hard 

 paraffin with vaseline). This gives an unbroken 

 ribbon of sections. 



To Mount Sections of Mosquitoes 



Unless the sections are thick it is necessary to 

 flatten them. 



Heat some water in a dish a little below the 

 melting point of the paraffin. Test the. right 

 temperature by dropping a section on the surface. 

 If it melts, the water is too hot. If it does not 

 flatten out, the water is not hot enough. 



Drop upon the surface a ribbon of five or six 

 sections ; it will become perfectly flat if the 

 temperature is right. 



1. Smear some slides with solution of 

 pyroxylon in oil of cloves (Appendix), taking care 

 to avoid an excess. Lower the slide rapidly into 

 the water, and with the aid of a needle draw it 

 out again with the sections lying flat upon it. 



2. Press lightly, but firmly, between smooth 

 blotting paper. Protect from dust, and allow to 

 dry for twenty-four hours, or dry more rapidly 

 over the flame, but avoid melting the paraffin. 



When dry, hold the slide a few seconds over 

 the flame, this drives off the oil of cloves and 

 melts the paraffin. 



Pour over the slide first xylol, then alcohol, 

 and finally place in water, 



