184
MARINE MOLLUSCS AS HOSTS F O R SYMBIOSES
Meretrix meritrix, Paphia philippinarum (= Tapes semidecussata),
Cyclina sinensis, Mactra veneriformis, M . sulcataria and Dosinia
bilunulata.
Description. Body oval or elongate pyriform, 55-76 p (average
67 p ) x 14-29 p (average 20 p), blunt anteriorly, dorsoventrally
flattened, ciliated on both surfaces ; conspicuous macronucleus subspherical, in center of body ; micronucleus spherical, anterior to macronucleus ; single contractile vacuole in posterior portion of body as are
numerous food vacuoles.
Other information. Nothing else is known about this species.
FIG. 88. Section through gills of Modiolus modiolus collected in Narragansett Bay,
Rhode Island, showing Ancistrum isseli on gill surface.
6 . Boveria subcylindrica Stevens, 1901. (Figs. 90 and 91)
(Subclass Holotrichia; order Thigmotrichida; family Hemispeiridae)
This species was originally described by Stevens (1901) in California,
but Issel(l903) has since found it on the gills of a number of pelecypods
in the Gulf of Naples including Tapes decussatus. It is definitely not
host-specific as its other hosts include Tellina nitida, T . planata, T .
exigua, Capsa fragilis, Donax politus, Venus gallina, Loripes lecteus,
Cardita sulcata and Pinna nobilis. Issel believed that his specimens were
sufficiently different from those described by Stevens to justify the
establishment of a new variety, concharum.
MARINE MOLLUSCS AS HOSTS F O R SYMBIOSES
Meretrix meritrix, Paphia philippinarum (= Tapes semidecussata),
Cyclina sinensis, Mactra veneriformis, M . sulcataria and Dosinia
bilunulata.
Description. Body oval or elongate pyriform, 55-76 p (average
67 p ) x 14-29 p (average 20 p), blunt anteriorly, dorsoventrally
flattened, ciliated on both surfaces ; conspicuous macronucleus subspherical, in center of body ; micronucleus spherical, anterior to macronucleus ; single contractile vacuole in posterior portion of body as are
numerous food vacuoles.
Other information. Nothing else is known about this species.
FIG. 88. Section through gills of Modiolus modiolus collected in Narragansett Bay,
Rhode Island, showing Ancistrum isseli on gill surface.
6 . Boveria subcylindrica Stevens, 1901. (Figs. 90 and 91)
(Subclass Holotrichia; order Thigmotrichida; family Hemispeiridae)
This species was originally described by Stevens (1901) in California,
but Issel(l903) has since found it on the gills of a number of pelecypods
in the Gulf of Naples including Tapes decussatus. It is definitely not
host-specific as its other hosts include Tellina nitida, T . planata, T .
exigua, Capsa fragilis, Donax politus, Venus gallina, Loripes lecteus,
Cardita sulcata and Pinna nobilis. Issel believed that his specimens were
sufficiently different from those described by Stevens to justify the
establishment of a new variety, concharum.