NO. 51.— 1900.] PEARL FISHERIES. 



179 



diseases which lead to the formation of pearls. In the 

 course of an address to the Malacological Society of London, 

 in 1896, Professor Howes, referring to the peculiar charac- 

 teristics of certain marine mollusca (chitons), remarked : 

 "In its bearings on the conditions of local distribution 

 in shallow water, on bathymetric extension, and specific 

 variation as related to these influences, the experimental 

 method appears to me to give promise of most important 

 results in Malacology. Just as the physiological graduates 

 off into the pathological, the full significance of many a 

 healthy or a diseased state becoming intelligible only on a 

 knowledge of its opposite, so, in the hands of the experi- 

 mentalist, the normal phenomena of animal life will most 

 assuredly in course of time become illumined by prolonged 

 and careful study of the organism under changed conditions. 

 And from all that is now going forward it is plain that the 

 pathologist holds the key to many a life problem." 



3. Captain Donnan read the following Paper bearing on the 

 subject : — 



