MUSCLE OF FIN. 139 



sect it carefully out. Haying done so, I 

 submitted it to the microscope, using this 

 time a ^-inch object glass. Under this 

 power the structure of the muscle is plainly 

 visible, and the regular transversely-striated 

 appearance leaves no doubt whatever of its 

 voluntary character. (Object No. 1.)* Not 

 content with this, I proceeded to dissect out 

 one of the pectoral fins of another fish, with 

 a portion of the muscle adhering thereto. In 

 this case also there was no doubt whatever 

 of the voluntary nature of the structure of 

 the muscle. I have also examined the 

 pectoral fin and muscle of the smelt, and 

 find the same striated appearance, and 

 consequently the same voluntary principle. 



* These objects, mounted on glass, have been presented to 

 me bv Mr. Hancock. 



