124 PRACTICAL HISTOLOGY. 



Preparations 15 and 16. Termination of 

 muscle in tendon. It' the tendons of a mouse's 

 tail are forcibly drawn out, after nipping off the end 

 of the tail in the manner described in the account 

 of the preparation of tendon (p. 83), it will generally 

 be found that portions of a number of small mus- 

 cular fibres are adherent to each tendon, for the 

 fibres have their insertions into the tendon, and are 

 ruptured by the force employed. These ends, 

 mounted in serum, serve conveniently for the study 

 of the mode in which the fibres of a muscle termi- 

 nate in a tendon, when the fibres of the latter run 

 in the same direction of those of the muscle. But, 

 easy as the tissue is to prepare, the observation is 

 complicated by the fact that the muscular fibres 

 form generally somewhat of a clump as they pass to 

 end in the tendon. The preparation may be im- 

 proved by being stained with picrocarmine solution. 

 This colors muscular tissue yellow, tendinous tissue 

 red, so that the distinction between the two is made 

 more obvious. It is best to take a few freshly 

 drawn-out tendons, and to mount their ends in a 

 drop of the picrocarmine solution, surrounding the 

 edges of the cover-glass with melted paraffin to pre- 

 vent evaporation of the liquid. 



It is easier to make out the way in which the 

 fibres of a very thin fiat muscle, such as the subcu- 

 taneous muscle over the frog's sternum, terminate 

 in the fibrous tissue to which the muscle is attached. 

 Here the fibres of the tendon do not take the same 

 direction as the muscular fibres. A frog, having 

 been killed by destroying the brain and spinal cord, 

 is laid upon its back, and the skin over the throat 

 is reflected downwards towards the sternum. The 

 flat muscle w^hich is thereby brought to view passing 

 to the skin is snipped across the middle with scissors, 

 seized on the cutaneous side of the snip with forceps, 

 and a square piece, including its insersion into the 

 skin, is cut out. It is placed as flat as possible upon 

 a dry slide, the curled-up- edges being turned down 



