RESEAIiCII IN SCIEXCE 



5G1 



stages l)y wliicli tlic larv;v ivadi llic 

 coiulitiiin of iiiiiiiatiiiv adults, an uii- 

 nia])))('il tiTi'itttry wlici-c all trails went 

 l)liml, and only in IMdd, when a youni; 

 (u'rnian invi'stipitor^ made the some- 

 what accidental observation of glo- 

 chidia living as parasites npon fishes, 

 was the (K'W discovered and Ihe \vt)rk 

 of following the later stages made pos- 

 sible. During this final period, the 

 post-glochidial (Icvelopnicnt hecame 

 well known and the earliest stages of 

 esrg and embrvo were reexamined in 

 the interests of fundamental research 

 up(m development throughout the ani- 

 mal kingdom. Most important of all 

 for illustration of tlie point here made, 

 is the fact that, from Leeuwenhoek's 

 beginning, all this work was part of an 

 attempt to understand the nature of 

 individual development in the animal 

 world. Through it all, the direct pres- 

 sure of utilitarian consideration is 

 nowhere to be found, but rather a belief 

 l:)y the investigators that the facts were 

 worth knowing because they gave a 

 broader horizon to the landscape of 

 nature. 



In 1891 the first pearl button was 

 cut from a fresh- water mussel shell. 

 The business soon became a substantial 

 industry and, within ten years, the 

 destruction of the mussel beds in 

 the Mississippi seemed imminent. At 

 the request of the manufacturers, the 

 United States Bureau of Fisheries un- 

 dertook a brief survey and offered some 

 wholesome advice, all of which was dis- 

 regarded with the opening of new 

 sources of supply in Arkansas, Indiana, 

 and along the Ohio. Seven years later, 

 under the stress of a still diminishing 

 supply, the manufacturers again ap- 

 proached the United States Bureau of 

 Fisheries with the result that the Bu- 

 reau made an extensive study of the 

 mussel with a view to its artificial 

 propagation. 'I'lio residts of tin's in- 



' Leydig. F.. MUthrilting iil>fr den ParnsU'.smvs 

 juntier Vnioniden an FUrhen in XoU." Tiibingen, 

 Inaug-Dis. Frankfort a. M. 



vcstigati<m have now been brought to- 

 gclhci-- and. since there are still many 

 rundiinicnial (piestions involved, the 

 gn\ci-nnient has constructed, at Fair- 

 |init. Iowa, a station for the investiga- 

 tion of llicsc and all other problems of 

 fresh-water biology, and as a part of 

 this station, a hatchery for the rearing 

 of mussels hy artificial means. 



While niucli i-emains to be done be- 

 foi'c the rearing of liutton mussels is 

 established upon a connnercial basis, 

 the results are encouraging, and we 

 may lio|ie that hcfoi-c many years the 

 supply of raw material will be drawn 

 from beds artificially produced and 

 maintained. As this work in applied 

 science advances, it is conceivable that 

 the men who have dealt with these 

 practical proljlems may win popular 

 recognition greater tlian that given to 

 any of their predecessors during the 

 two hundred and fifty years since 

 Leeuwenhoek. Be this as it may, I do 

 not hesitate in saying that to the earlier 

 workers l)elongs the larger measure of 

 recognition, that theirs was the more 

 unique attainment; since between the 

 two there is the difference between the 

 man who broadens a beaten trail and 

 him who penetrates territory wholly new. 



The Future Structure of Society and 

 Character of the Human Race Are 

 Likely to he Controlled hy Knowl- 

 edge of the Worl-ings of Hered- 

 ity; This Knowledge Was 

 Gained hy Investigations 

 not Aimed to he Utili- 

 tarian 



In the field of heredity we have 

 known so little, have so failed in the 

 discovery of landmarks until very re- 

 cent years, that biological science is 

 oidy beginning to get its bearings and 

 hew its wav into the wild. We stand 



- Lcfevre. G., and Curtis. \V. C. Studies on the 

 Reproduction and Artificial Propagation of Fresh- 

 water ^[ussels. BuUi't.in of the Bureau of Fish- 

 eries, Vol. XXX, 1910. See also the miscellaneous 

 papers 1)y other investigators, in United States Bu- 

 reau of Fisheries Bulletins since 1910. 



