174 PREPARATION AND MOUNTING 



place it in a vessel of water. Hold it down firmly with a 

 pair of tweezers, and with the back of a dissecting knife 

 draw the head steadily from the body. The head brings 

 with it the stomach, gizzard, and chief portion of the digestive 

 tubes. Place all these under a dissecting microscope, when 

 the gizzard, being just below the stomach and darker in 

 colour, is easily distinguished, and may be separated by two 

 cuts with the knife. It then forms a short tube, the teeth 

 being inside. The opening-out of this tube, especially if it 

 be small, requires delicate handling : if the point of a fine 

 knife can be fairly inserted, then one firm cut downward 

 upon the glass will lay open the gizzard. Here great care 

 is needed ; and sometimes it is well to put a fine needle up 

 the tube, and cut down upon the needle. Among the 

 small weevils the membrane is delicate, so that great care 

 is necessary. 



We have now considered most of those objects which 

 require any peculiar treatment in section-cutting, &c. ; but 

 in no branch of microscopic manipulation is experience ore 

 than in this. 



