84 ELEMENTARY PHYSIOLOGY. [VIII. 



Cut through the skin above and below the muscle, 

 and tear away the connective tissue around it, 

 then, keeping it stretched, pour a little 1 p.c. 

 osmic acid over it. In a minute or so the muscle 

 will be fixed ; with fine forceps tear away carefully 

 from the muscle any connective tissue that can 

 be seen on its surface and cut it out being care- 

 ful to cut the upper end as close as possible to 

 the skin ; place it in osmic acid for a few minutes, 

 wash with water, mount it in either dilute 

 glycerine or after treatment with alcohol etc. 

 in Canada balsam, keeping that surface upper- 

 most which was next the body. (This specimen 

 should be preserved for examination later, Lesson 

 x. C. 1.) 



Observe at the upper end of the muscle the 

 endings of the muscular fibres, these will prob- 

 ably be covered by a good deal of connective 

 tissue, but the rounded or conical ends of the 

 muscle-substance of the fibres and the continua- 

 tion of the sarcolemma into the connective tissue 

 (tendon) will be seen. 



7. Kemove with as little injury as possible one of 

 the thin muscles from the leg of Hydrophilus 1 , 

 tease it out a little without adding fluid and 

 mount as in 4. The fibres will for a brief period 

 be seen in a normal condition. In many, the 

 alternate dim and bright striae will be very dis- 



1 if not obtainable, take the large common water-beetle (Dytiscua 

 marginalis), or failing that a cockroach or a fly. 



