PLATE 2 
EXPLANATION OF FIGURES 
7 Pectoral fin of a carp, about 3 inches long, 3^ hours after infection with 
glochidia of Anodonta cataracta. An optimum infection. 
8 Ventral half of the tail of a carp, as above, 24 hours after infection. 
An optimum infection. 
9 Tip of an over-infected fin, as above, 12 hours after infection. Showing 
no appreciable over-growth because of the crowding. The shadows represent 
glochidia upon the under surface. 
10 Fin, as above, 7 days after infection. Showing the complete failure to 
embed in all places where the glochidia are greatly crowded. See explanation in 
the text p. 106 of the conditions along the upper margin. 
11 Fin, as above, 36 hours after infection. Showing the complete over- 
growths of all glochidia which have secured the proper attachment. 
12 Young of Symphynota costata, leaving the fin of a carp after a parasit- 
ism of 74 days. 
13 Anterior gill of a black bass infected with Lampsilis ligamentinus, show- 
ing distribution upon the gill as a whole and the appearance of the cysts. 
14a Glochidium of A. cataracta upon fin of carp. Developing normally 
after a shift of 90 degrees from the position first taken. 
14b Two glochidia of Anondonta cataracta, overgrown after 36 hours upon 
surface of a carp's fin. 
