42 American Fisheries Society 



ligation is to find a method of propagation, such a test 

 meets the ultimate requirements. 



The results obtained from these artificial infections 

 are frequently very definite, giving conclusive support to 

 the indications obtained from natural infections. 



The following cases are concrete illustrations of this : 

 Last May I undertook a series of experiments to de- 

 termine to what extent the common fishes could be 

 used in artificial propagation of certain mussels of the 

 family Lampsilinae (Ortmann). The species were the 

 Mucket, Lampsilis ligamentina Lam.; the Fat or Lake 

 Mucket, Lampsilis luteola Lam., and the Yellow Sand 

 Shell, Lampsilis anodontoides Lea. 



The glochidia of these species were brought in contact 

 with some sixty fish of 12 different species in each ex- 

 periment. The infections with each species of mussel 

 were kept separate so that I had three separate experi- 

 ments. These I carried on under as nearly identical con- 

 ditions as possible, so that they were practically parallel. 

 The results summarized show what usually occurs in such 

 an experiment. The glochidia took hold more or less on 

 every fish, dropping off of some species in from 1 to 4 

 days without development, in other remaining on to the 

 full period, which was three weeks in each of these cases. 

 The muckets and fat muckets remained the full period 

 on the basses (Centrarchidx) ; sea basses (Serranidse) , 

 and perches (Percidas). They dropped off of the cat- 

 fishes (Siluridse), the sheepshead (Aplodinotus grun- 

 niens Raf.) and the gar (Lepisosteus platostomus Raf). 

 The yellow sand shells remained on the gars, and dropped 

 off of all the other species. We have here rather strik- 

 ing results. Chances of error were largely eliminated, 

 from the fact that the experiments were carried parallel. 

 As a further check I have repeated tests where there 

 seemed to be any possibility of doubt. 



The mucket and lake mucket are indicated as mussels 

 having an extensive range of parasitism on several gen- 

 era of fishes, while the yellow sand shell, a closely related 



