XVI] NERVE-ENDINGS IN MUSCLE 129 



connective tissue as possible. Mount in formic glycerine, press 

 the cover-slip to separate the fibres a little, and examine for end 

 plates, using a lamp for illumination. 



7. Nerve-plexus in unstriated muscle. Cut 



out the oesophagus of the frog used in 1. Cut it open, 

 scrape gently the mucous surface. Pin it out with 

 hedgehog quills over a hole in a piece of cork, muscular 

 coat uppermost. Cut off the quills close to the mem- 

 brane. On the muscular coat place a couple of drops 

 of '05 p.c. saline methylene blue. Cover up with a 

 watch-glass lined with wet blotting-paper for 20 to 30 

 minutes. Then wash off the blue with a drop or two 

 of *6 p.c. salt solution. Place the piece of cork on a 

 slide and examine with low objective and high ocular, 

 and without diaphragm. 



Note the very close plexus of fine blue-stained 

 nerve fibrils, generally varicose in the muscular coat. 



Put on a cover-slip and examine with a high power. 



8. Make a methylene blue preparation of the nerve plexus 

 in the muscular coats of the rectum of the frog, treating it in 

 the manner given in 6. 



9. N euro-muscular organs (muscle spindles 1 ]. Take a piece 

 of mammalian muscle which has been stained by Sihler's 

 heematoxylin method (cp. Notes) ; place it in glycerine on a 

 large slide and cover with an ordinary slide, squeeze the slide, 

 hold up to the light, and look for a dark stained spindle-shaped 

 body (if none is seen examine with a low power of the microscope ; 

 if none is then seen, take a fresh strip of muscle). Cut this out 

 under a dissecting microscope and note 



The swelling of the spindle caused chiefly by several con- 

 nective tissue membranes. 



L. 9 



