The fungus Lagenidium callinectes Couch (1942) on eggs of the blue crab in Chesapeake Bay.

In 1941 a parasitic fungus was first observed on the eggs of many obtained from natural spawning areas in Chesapeake Bay (Sandoz, Rogers, Newcombe, 1944). Dr. John N. Couch of the University of North Carolina examined infected samples and recognized the parasite to be a new species, he named Lagenidiiin callinectes Couch (1942). Marked annual fluctuations in the commercial catches of the blue crab Callinectes sapidus Rathbun (1895) have taken place. The discovery of the egg raised the questions of how it affects the development of the crab embryo, percentage of the eggs of a crab may be infected, and how widely the distributed in Chesapeake Bay. Conceivably, such a parasite could serious biological factor limiting the production of crab larvae and causing, in part, yearly fluctuations in the commercial population. Laboratory and field studies were carried out: (1) to ascertain the of existence of the parasite in the individual crab eggs as well as on and mass (commonly called sponge ); (2) to show how readily infection may mitted under certain conditions; (3) to indicate the effects of salinity and temperature on the survival and development of the fungus; and (4) to show Chesapeake Bay in which it occurs and the approximate degre