34 LABORATORY MANUAL OF GENERAL PHYSIOLOGY 



7. Migration of Granules in Chromatophores. — Remove a few scales 

 from Fundulus. Rinse in tap water and distilled water. Place in 0.1 

 M NaCl. Observe the chromatophores under the microscope. Na 

 produces expansion (dark color of animal). Discard any scales showing 

 "contraction" (clumped granules). Now place the scales in 0.2 M KCl 

 after allowing NaCl to drain off. Observe K contraction followed by 

 slow expansion. If time permits try 0.2 M CaCl2 (cf. Ponder, ' 'Essentials 

 of General Physiology," pp. 149-150). 



VIII. CILIARY MOVEMENT 



1. Effects of Ions on Ciliary Action. — Obtain small fragments of gill 

 (not mantle) from a live clam. Keep in sea water. Bits of gill are to be 

 placed in labelled watch glasses containing the solutions listed below. 

 Wash the tissue in the solution to be used to remove sea water. Observe 

 under microscope and determine the duration of the ciliary beat. Keep 

 microscope free from solutions. Text p. 283- 



(a) Pure solutions of the chief cations found in sea water (and in blood) 

 in M/2 concentration (isotonic with sea water). NaCl; KCl; MgCl2; 

 CaCl2; sea water control. 



(b) Combinations of two cations 



25 vols M/2 NaCl plus 1 vol. M/2 KCl 

 25 vols M/2 NaCl plus 1 vol. M/2 CaClz 

 25 vols M/2 NaCl plus 1 vol. M/2 MgClz 



(c) Combinations of 3 or 4 cations 



25 vols NaCl plus 1 vol KCl plus 1 vol. CaCl2 



25 vols NaCl plus 1 vol. CaCl2 plus 1 vol. MgCU 



25 vols NaCl plus 1 vol. KCl plus 1 vol. MgCl2 



25 vols NaCl plus 1 vol. CaCl2 plus 1 vol. KCl plus 1 vol. MgCl2 



Determine the duration of the ciliary movement in each case. Solutions 

 of three salts and sea water controls should be observed next day. Cover 

 watch glasses to prevent evaporation. Is KCl, CaCl2, of MgClo the most 

 effective in antagonizing the toxic effect of NaCl? The effects are essen- 

 tially those of ions on colloidal systems. Text p. 282. 



If possible, distinguish between frontal (at distal ends of filaments) 

 and lateral cilia. Cilia reverse their direction too rapidly to be followed 

 by the human eye but the form of the moving cilium may be demonstrated 

 with the stroboscope. Cf. Jennison and Bunker, Jour., Cell Comp. 

 Physiol., 5:189, 1935. The data from all groups may be averaged. 

 Consult Gray's book, "Ciliary Movement," Chap. V. Compare data 



