APPENDIX 



METHODS OF ANATOMICAL AND HISTOLOGICAL 

 INVESTIGATION 



(Additional remarks on methods will be found on pp. 7, 25, 69, 158.) 



Much may be made out respecting the strnctiire of the General iu- 

 Lirva by simple examination of the living and uninjured 

 animal under the microscope. A little dissection maj^ 

 also be done with the help of a dissecting microscope. 

 This is particularly important for the purpose of getting 

 true notions as to the relative situation of the organs. 

 We have also made great use of comparatively thick 

 but transparent sections made by the celloidin process. 

 These are particularly serviceable in topographical ana- 

 tomy. Lastly, continuous thin sections are indispensable 

 for histological study. 



The following directions incorporate the experience of Mr. 

 Mr. Norman Walker, Demonstrator in Botany at the mSS'^of 

 Yorkshire College, who has made many excellent series tkTn for" 

 for us :— cuttino:. 



'fixing and preseeving larvae. 



' The two following fixing methods have been found to 

 answer well. 



' I. Flemmhig's chromic-acetic-osmic acid. Larvae are 

 placed in this fluid for one hour. Each larva is halved 

 and again placed in the mixture for another hour. They 

 are then washed in mnning water for twenty-four hours. 



MI ALL. Jf 



