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Malate Dehydrogenase Isozymes Of Different Stages Of Chesapeake Bay Jellyfish, Alin L. Lin, Paul L. Zubkoff
Malate Dehydrogenase Isozymes Of Different Stages Of Chesapeake Bay Jellyfish, Alin L. Lin, Paul L. Zubkoff
VIMS Articles
In the Scyphozoa, pronounced morphological changes occur during strobilation which are undoubtedly preceded by changes in gene activity, metabolic pathways, and biosynthetic mechanisms : the long tentacles of the scyphistoma are retracted and a series of transverse constrictions are formed at the oral end; each transverse section develops into an ephyra and subsequently into an adult medusa. This morphological development of Chrysaora quinquecirrha has been thoroughly studied by Littleford ( 1939) and Calder ( 1972) . Influences of environmental and chemical factors on strobilation of both Aunelia aunita and C. quinequecinrha have been investigated by many workers (Custance, 1964 ; …
Physiology And Ecology Of Bacteriophages Of Marine Bacterium Beneckea-Natriegens - Salinity, A Zachary
Physiology And Ecology Of Bacteriophages Of Marine Bacterium Beneckea-Natriegens - Salinity, A Zachary
VIMS Articles
The effects of variation in ionic levels on the stability and replication of two bacteriophages (nt-1 and nt-6) host specific for the marine bacterium Beneckea natriegens were examined. Monovalent cations influenced the adsorption of the nt-1 but not the nt-6 phage; however, one-step growth studies showed that NaCl was required for replication of both phage. The NaCl optimum for nt-1 production was 0.25 M NaCl, the same as the growth optimum for B. natriegens. However, the optimum for nt-6 production was 0.16 M NaCl. These NaCl optima for host and phage are at estuarine rather than oceanic levels. The nt-1 …
Dermocystidium-Marinum Infection In Oysters, Frank O. Perkins
Dermocystidium-Marinum Infection In Oysters, Frank O. Perkins
VIMS Articles
A review of knowledge concerning the life cycle, structure, taxonomy, and pathology of Dermocystidium marinum is presented. The pathogen causes mortalities of the American oyster, Crassostrea virginica, along the Atlantic and Gulf coasts of the United States.
Effects Of Substratum On Growth Of The Bivalve Rangia Cuneata, Gray, 1831, Richard K. Peddicord
Effects Of Substratum On Growth Of The Bivalve Rangia Cuneata, Gray, 1831, Richard K. Peddicord
VIMS Articles
THE BRACKISH WATER bivalve Rangia cuneata Gray, 1831, a member of the family Mactridae, has been reported from Virginia estuaries in the past few years. This species, until recently common only along the Gulf Coast, occurred in estuaries from New Jersey to Mexico during the Pleistocene ( RICHARDS, 1938) , and now seems to be reoccupying its former range. Live R. cuneata on the east coast were first reported from North Carolina in 1955 (WELLS, 1961), Florida in 1961 (WOODBURN, 1962), Virginia in 1960 (WAss, 1972), the Potomac River in 1964 (PFITZENMEYER & DROBECK, 1964), upper Chesapeake Bay in 1966 …
Zoospores Of The Oyster Pathogen, Dermocystidium Marinum. I. Fine Structure Of The Conoid And Other Sporozoan-Like Organelles, Frank O. Perkins
Zoospores Of The Oyster Pathogen, Dermocystidium Marinum. I. Fine Structure Of The Conoid And Other Sporozoan-Like Organelles, Frank O. Perkins
VIMS Articles
An apical complex comparable to that found in the Sporozoa is described from zoospores of Dermocystidium marinum Mackin, Owen, and Collier, a pathogen of the American oyster (Crassostrea virginica Gmelin). The complex consists of a conoid, polar ring, up to 39 subplasmalemmal microtubules, rhoptries, and micronemes. Micropores and a subpellicular membrane equivalent were also found. Acid phosphatase activity was found in cisternae of the endoplasmic reticulum, inclusion bodies, and vesicles within the conoid lumen. No polysaccharides were detected in the rhoptries and micronemes using the Thiéry method. Observations indicate that D. marinum is a protozoan in the subphylum Apicomplexa and …
Fine Structure Of Marteilia Sydneyi Sp. N.: Haplosporidan Pathogen Of Australian Oysters, Frank O. Perkins, Peter H. Wolf
Fine Structure Of Marteilia Sydneyi Sp. N.: Haplosporidan Pathogen Of Australian Oysters, Frank O. Perkins, Peter H. Wolf
VIMS Articles
A new species of oyster pathogen, Marteilia sydneyi, from Australian oysters, Crassostrea commercialis, is described incorporating light and electron microscope observations. The pathogen is a haplosporidan which exists as a plasmodium in the oyster hepatopancreas. Upon sporulation, 8 to 16 uninucleate sporangial primordia are internally cleaved (endogenously budded) from each plasmodium; thus conversion to a sporangiosorus occurs. Each sporangium enlarges and internally cleaves into 2 or 3 spore primordia each of which, in turn, internally cleaves into 3 uninucleate sporoplasms of graded sizes, the largest containing the smaller 2 in a vacuole and the intermediate-sized one containing the smallest in …
Occurrence Of Hematopoietic Neoplasms In Virginia Oysters (Crassostrea-Virginica), Em Frierman
Occurrence Of Hematopoietic Neoplasms In Virginia Oysters (Crassostrea-Virginica), Em Frierman
VIMS Articles
The three predominant pathogens of oysters in Virginia are the haplosporidans Minchinia costalis and M. nelsoni and the protist Dermocystidium marinum (Wood and Andrews, 1962; Haskin, Stauber, and Mackin, 1966; Mackin, Owen, and Collier, 1950).