Biological Survey — Erie-Niagara Watershed 205 



infection by the bass tapeworm. The following data briefly sum- 

 marizes the infection with the plerocercoids of this parasite and 

 indicates something of its economic importance in small bodies of 

 water. 



Per cent 

 infection 

 No. examined Species with larval 



P. ambloplitis 



7 Small-mouthed black blass (M. dolomieu) .... 100% 



8 Large-mouthed black bass {A. salmoides) .... 100% 



9 Yellow perch (P. fiavescens) 100% 



14 Pumpkinseed sunfish {E. gibhosiis) 100% 



8 Chain pickerel (E. reticidatus) 25% 



In order to avoid confusion with other parasites the material 

 was sectioned and carefully studied. The authors feel confident 

 that this constitutes a new and accurate record for these hosts. 

 Infected yellow perch were also found in the Niagara river in 

 small quantities. 



Definitive Hosts. — Once more turning to the experimental work 

 we find the only record of the final or definite host lies in the 

 paper of Hunter^ in which the large-mouthed black bass {A. 

 salmoides) was artifically infected. This was accomplished by 

 feeding them small bass carrying the plerocercoid larvae in the 

 body cavity (cf. Fig. 4). During the summer of 1928 two experi- 

 ments were run to show that the infection could be transferred 

 from the second intermediate hosts to the small-mouthed black 

 bass which were used as the definitive hosts. Unfortunately 

 yearling bass were scarce. Four experimentally infected yellow 

 perch were fed to 2 M. dolomieu and 4 top minnows were fed to 

 3 of the small-mouthed black bass. In the first experiment both 

 fish yielded unsegmented plerocercoids of P. amhloplUis from the 

 upper part of the digestive tract (Fig. 13), while in the second 

 two of the fish gave parasites in a similar stage of development ; 

 the third bass is still unexamined. 



Distribution and Economic Importance of the Bass Tape- 

 worm. — As has been previously stated the bass tapeworm (P. 

 amhloplitis) is of considerable economic importance. It has been 

 noted that there are 4 fish which may harbor the adult worm, the 

 rock bass {A. rupestris), small and large-mouthed black bass (3f. 

 dolomieu and A. salmoides) and the fresh water dogfish (Amia 

 calva). All four hosts are reported from the Great Lakes drain- 

 age^ and likewise from the Mississippi river basin. ^ The senior 



^ Hubbs, C. L. A check-list of the fishes of the Great Lakes and tributary 

 waters, with nomenclatorial notes and analytical keys. U. of Mich., Mns. 

 Zool., Misc. Publ. No. 15; 77 pp. 1926. 



'Forbes, S. A. and K. E. Richardson. The fishes of Illinois. Vol. III. 

 Ichthyology, 111. St. Lab. Nat. Hist.; 342 pp. 1908. 



