DISEASES OF MARINE FISHES
25
beneath the skin or in the body of inshore fishes. An excellent, example
is the trematode Crgpfocofyle lingua (Creplin), whose life cycle in the
western North Atlantic (Fig. 7 ) involves the periwinkle, Lifforina
Zitform (IA.), the Atlantic herring, and the gull, LnrtiS cirgmtntus
Pontoppidan. Originally a parasite of comparable species in northFIG. i . Life cyrle of ('ryplorolylr lingror in the uwtrrn North Atlantic (tit)ov(,)
and rr:sult,s of parmitizat,ion of Atlmitir herring (hehiw).
western Europe (Christensen and Roth, 1 !bt9), the parasite was introduced in North American waters near t h r niiddlr of the nineteenth
century, proloablg with its snail host (Stnnknrd. 1930). Cercariae of
Cryptocotyle invade and encyst in the fins and integument of lierring
and a number of other iiishore western Atlantic species, causing the
formation of coiispicuous pigmented cysts or " black spots ". It has
25
beneath the skin or in the body of inshore fishes. An excellent, example
is the trematode Crgpfocofyle lingua (Creplin), whose life cycle in the
western North Atlantic (Fig. 7 ) involves the periwinkle, Lifforina
Zitform (IA.), the Atlantic herring, and the gull, LnrtiS cirgmtntus
Pontoppidan. Originally a parasite of comparable species in northFIG. i . Life cyrle of ('ryplorolylr lingror in the uwtrrn North Atlantic (tit)ov(,)
and rr:sult,s of parmitizat,ion of Atlmitir herring (hehiw).
western Europe (Christensen and Roth, 1 !bt9), the parasite was introduced in North American waters near t h r niiddlr of the nineteenth
century, proloablg with its snail host (Stnnknrd. 1930). Cercariae of
Cryptocotyle invade and encyst in the fins and integument of lierring
and a number of other iiishore western Atlantic species, causing the
formation of coiispicuous pigmented cysts or " black spots ". It has