APPENDIX 



PRACTICAL WORK 

 A. GENERAL INSTRUCTIONS 



It is absolutely imperative that the student should make a careful 

 personal examination of each of the animals about which 

 Practical Work.he reads, and should verify to the utmost extent possible 

 the statement made in his text-books. However clearly 

 he may seem to have understood these statements, he will never really 

 comprehend any organism until he has handled it himself, nor will he 

 by any other means realise that his subject-matter is the living animal 

 and not what is said about it. In the following pages certain instruc- 

 tions are given to facilitate this practical work, but they must not be 

 considered as exhaustive, and the student should follow out any lines 

 of investigation which his own ingenuity can suggest to him. 

 The following apparatus, etc., will be needed : — 



1. Some dissecting instruments, including two or three dissecting 



knives or scalpels of various sizes, a large and a small 

 Apparatus. pair of forceps, a large and a small pair of fine-pointed 



dissecting scissors, a blunt probe or seeker, and some 

 needles mounted in handles. A box of such instruments can 

 be bought for about £1. 



2. A dissecting dish for dissecting under water. A shallow pie- 



dish with a sheet of cork weighted with lead on the bottom 

 will serve this purpose. 



3. A magnifying glass with a stand and arm to hold it over the 



dish while both hands are used for dissection. 



4. Some stout pins, a sponge, and a duster. 



5. Some wide-mouthed jars with corks or stoppers to keep 



specimens for dissection or from day to day while they are 

 being dissected. A 2 per cent, solution of formalin in water 

 is the best preserving fluid in most cases, but 70 per cent, 

 methylated spirit may be used. 



6. Plenty of clean water. 



7. Glass pipettes. Some of these should be drawn out to a fine 

 opening : others should have wider mouths. 



8. Chloroform for killing, and various other reagents for staining, 



etc. , which will be mentioned later. 

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