96 



CILIAET MOTIONS. 



The peculiar motory phenomena that fall under this class were 

 known to the older naturalists, but their more successful inves- 

 tigation was reserved for our day. 



Ciliary motions may be most conveniently studied with the 

 microscope, on portions of the mucous membranes ; that from 

 the mouth of the frog is most readily obtained, placed on a 

 glass slide in a drop of water, then covered with a small piece 

 of thin glass, and viewed with a fourth or an eighth of an inch 



with certainty be shown in the circumference of the muscular fibres, how. 

 ever prepared by hardening, &c. The intimate structure is excellently 

 displayed, both by Bowman and Henle, as also in the accompanying figures. 



Fig. 63. j .. Fig. 63. Two 



primary mus- 

 cular fasciculi 

 from the dor- 

 sal muscles of 

 a rattle-snake, 

 which had been 

 long kept in 

 spirits. At * 

 and* fine fibres 

 are seen dis- 

 tinctly brought, 

 into view by 

 separating the 

 muscular bun- 

 dles ; they seem 

 each to consist 

 of several pri- 

 mary or ulti- 

 mate fibres. B, Two of these fine filaments, seen under a power of 800, 

 which exhibit crossmarkings. The sinuous filament is cellular tissue. 



Fig. 64. 



Fig. 64. A, A bun- 

 dle of fibres with- 

 out cross striae, from 

 the adductor muscle 

 which closes the 

 shell of Unio pic- 

 torum. B, A muscu- 

 lar bundle without 

 cross-streaking from 

 the Distoma dupli- 

 catum. C, The same 

 bundle thrown into 

 ziz-zags at the mo- 

 ment of contraction -, 



