316 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



The writers are especially indebted to Mrs. Jean A. Ross for 

 staining and mounting the specimens, to Mrs. Katharine Hill Paul 

 for most of the drawings that illustrate this report, and to Dr. 

 Carl L, Hubbs for checking the names of the fish hosts. 



All hosts are from the vicinity of La Jolla in southern Cali- 

 fornia unless other localities are cited. All the croakers and cor- 

 binas (family Sciaenidae) were taken by line fishing from the 

 Scripps Laboratory pier at La Jolla. Most of the other fishes were 

 collected by seining in shallow waters and tide pools or were ob- 

 tained from commercial fishermen. 



In this study 17 species of digenetic trematodes are recognized 

 from marine fishes, of which 8 are regarded as previously un- 

 described. In the collections available for study there are unsatis- 

 factory representatives of two additional species, but the material 

 is not adequate to serve as the basis for describing these as new 

 species. One is a species of the genus Phyllodistomum (family 

 Gorgoderidae) from Fundulus parvipifmis parvipinnis Girard, and 

 the other is an undescribed species of the genus Lepidapedon (fam- 

 ily Lepocreadiidae) from Mycteroperca pardalis Gilbert, from 

 Mazatlan, Gulf of California. The former is represented by a 

 single individual and the latter by two broken specimens, both of 

 which lack the anterior extremity including the oral sucker. We 

 prefer to withhold descriptions of these in the hope that some 

 other worker may discover more adequate material on which to 

 base the species. 



For each new species described in this report a holotype has 

 been designated and is deposited in the United States National 

 Museum as a stained whole mount in clarite. All additional speci- 

 mens of the new species are regarded as paratypes, and as far as 

 available these are deposited in our own collections at Lincoln, 

 Nebr., and Urbana, 111., respectively, and in the United States 

 National Museum. 



A total of nine families of digenetic trematodes are represented 

 in the collection under consideration, of which the family Ope- 

 coelidae had the widest representation of genera and species as 

 well as of individual specimens. In the text descriptions are ar- 

 ranged by families of the trematodes. A list of fish hosts, with the 

 trematodes encountered in each, is given on pages 336-337. 



Previously there have been few studies of trematodes of fishes 

 from the Pacific coast of this continent. Chief of these are the 

 publications of Lloyd, McFarlane, Noble, Annereaux, and Park, 

 while Manter (1940) has described a few species from the Mexican 

 coast. The trematode fauna of southern California has been but 

 little known. Sleggs (1927) reported Otodistomum cestoides 



