410 Illinois State Laboratory of Natural History. 



species, Alasmodonta rugosa and Lampsilis ligamentinus, 

 show no infestation with the generally prevalent Aspidogaster, 

 and this is especially noteworthy in the case of the latter, 

 whose infestation with other parasites is both frequent and 

 severe. 



Table III. brings into comparison the number of kinds of 

 parasites found infesting individuals of each host species and 



Table III. Degree of Infestation of Individual Hosts. 



host SPECIES. 



Names. 



Quadrula multiplicata . . . 

 tuberculata 



metanevra 



lachrymosa 



asperrima 



pustulata 



pustulosa 



plicata 



trigona 



rubiginosa 



ebena 



Unio gibbosus 



complanatus 



Alasmodonta confragosa. 

 complanata 



rugosa 



marginata . 



Strophitus edentulus 



Anodonta irnbecilis 



suborbiculata . 

 corpulenta 

 Obliquaria reflexa 



Plagiola elegans 



donaciformis . 



Lampsilis parvus 



ellipsis 



ligamentinus 



luteolus , 



anodontoides 

 rectus ....... 



ventricosus. . 



alatus 



gracilis 



Totals 1577 



X - 

 SS D 



B £ 



28 

 41 

 36 

 29 

 21 

 20 

 87 

 89 

 27 

 40 

 23 

 35 



137 

 35 

 64 

 18 

 51 

 36 

 49 

 20 

 45 

 32 

 48 

 37 

 31 

 14 

 91 

 25 

 62 

 49 



108 

 60 

 89 



CD «■ 



3 « 

 crq o 



V M. 



<o ST 

 O 2 



3 



5 

 4 

 2 

 4 

 3 

 6 

 4 

 3 

 4 

 1 

 5 

 4 

 5 

 6 

 5 

 4 

 6 

 5 

 4 

 6 

 4 

 5 

 5 

 3 

 4 

 6 

 6 

 6 

 7 

 5 

 5 

 6 



Percentage of Individuals 

 Infested. 



o 



<t> 

 TO 



CD 



a> 



39 

 93 

 78 

 76 



100 

 90 

 68 

 79 

 37 

 38 

 30 

 60 

 88 

 34 

 56 

 72 

 92 

 72 

 94 



100 

 96 

 59 

 21 

 59 

 68 



100 

 56 

 68 

 87 

 89 

 87 

 95 

 97 



74 32 





29 

 20 

 33 

 55 

 33 

 25 

 32 

 43 

 33 

 35 

 30 

 40 

 64 

 26 

 44 

 28 

 31 

 58 

 18 



50 

 17 



48 

 58 



43* 



52 



18 



24 



25 



13 



16 



3 



9t 



11 



59 

 42 

 21 

 24 

 55 

 26 

 34 

 4 

 3 



17 

 24 



6 

 13 

 39 

 47 



6 

 39 



5 

 11 



6 



4 

 11 

 10 

 57 

 11 



4 

 40 

 31 

 37 

 22 

 45 



Co 

 9? 



3 



15 

 3 



43 



10 

 8 

 2 



25 



6 

 14 



8 

 27 

 30 

 20 



3 



43 

 2 

 8 

 19 

 20 

 19 

 33 

 23 



er 



a 



10 



10 ... 

 65 . . 

 30 20 



4 

 10 

 12 



6 



27 

 13 



5 |0. 6 



