THE MUSEUM. 



A Monthly Magazine Devoted to Research in Natural Science. 



Vol. V. 



ALBION, N. Y., JANUARY 15, 1899. 



No. 3 



A Brief History of the Gathering 



of Fresh-Water Pearls in 



the United States. 



Natural and Artificial Replenishment of 

 the hrcsh Water Mussels. 



BY GEORGE F. KUNZ. 



The inquiry as to whether the ex- 

 hausted beds recover, and in what 

 time, is closely connected svith the 

 preceding one. It is unanswered in 

 twenty-two of the papers, and seven 

 others report no knowledge or opinion 

 on the subject. Sixty-four replies are 

 given, of which several are indefinite 

 or conjectural. Out of about sixty 

 papers, therefore — or about two-thirds 

 of the whole — the following data is 

 taken: Sixteen report the belief that 

 the beds are replenished from year to 

 year; four in one or two years; three 

 in two or three years, and four in four 

 years. Four name periods between 

 four and eight years, and six between 

 six and twelve years, and one gives 

 twenty years, one twenty-five, and two 

 estimate the recovery as requiring a 

 century or more. Three papers say 

 that many years are necessary; five 

 say "a few" or "soon"; two report no 

 exhaustion as noticed, and six report 

 no recovery. Four papers are indefi- 

 nite or uncertain. Two of the papers 

 that give estimated date for recovery 

 do so with an expression of doubt ^"if 

 at all," "if ever') as to whether it 



really occurs. The Tennessee paper 

 before referred to says that the shells 

 return each year, but in less numbers. 

 .As it is customary, more or less, to 

 leave the young and small shells, the 

 ijuestion resolves itself largely into 

 two, namely: How far have they 

 been carefully spared, and how long 

 does it t.ike them to retain their 

 growth. This probably differs in dif- 

 ferent species, as it is estimated in 

 soiii'i of the answers, and it may also 

 be ini] lenced by various external con- 

 ditior'=. The Tennessee paper esti- 

 mates the recovery as slow from the 

 fact previously brought out very mark- 

 edly that the young shells are those 

 that are most exposed to all natural 

 enemies and accidents. The New 

 York paper, which thinks that there is 

 no recovery, states that few young 

 shells are found. A Texas pearler 

 says that the young shells are found in 

 two years, but contain no pearls. One 

 (mentioned under the last head) says 

 that many beds are recovering by the 

 growth of the young that were left be- 

 fore. On the other hand, in Indiana, 

 one states that when a bed has been 

 worked out plenty are found the next 

 season, and an Iowa pearler reports 

 young shells abundant everywhere. 

 One Tennessee answer gives a very 

 fair average statement to the effect 

 that the beds recover every season, 

 and would perhaps recover entirely in 

 a few years if not molested. 



NATIONAL AND STATE PROTECTION. 



The concluding inquiry, as to wheth- 



