Investigations for the Promotion of the Oyster Industry of North Carolina |
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Investigations for the Promotion of the Oyster Industry of North Carolina Henry Frank Moore,Caswell Grave No preview available - 2022 |
Investigations for the Promotion of the Oyster Industry of North Carolina Henry Frank Moore,Caswell Grave No preview available - 2018 |
Investigations for the Promotion of the Oyster Industry of North Carolina Henry Frank Moore,Caswell Grave No preview available - 2018 |
Common terms and phrases
abundant acres adductor muscle adult amount animal Beaufort region beds in Newport body bottom bushels oysters bushels shells evenly bushels shells planted cent of planted cilia clusters covered Creek Cross Rock crowded cultch currents diatoms didyma dredging elongated oysters Eupodiscus evenly scattered examination experimental bed experiments favorable feeding Fish Hawk gills grow growth hinge Hyde County larvæ layer living oysters localities low tide mantle marshes Melosira sculpta mouth mussels natural beds natural oyster beds Newport and North Newport River normal North Carolina North River organs oyster culture oyster food oyster grounds oyster planting oystermen Pamlico Sound planted beds planted oysters living planted shells plate VIII Ratio of width reef sand season seed oysters Sept shape species specific gravity stomach survey Swan Quarter taken tongers tonging grounds valves velum Wards Creek width to length Winslow Wyesocking Bay young oysters
Popular passages
Page 320 - This layer is seen in the section to be pushed in a little toward the upper layer, so that the lower surface of the disk-shaped embryo is not flat, but very slightly concave. This concavity is destined to grow deeper until its edges almost meet, and it is the rudimentary digestive cavity. A very short time after this stage has been reached, and usually within from two to four hours after the eggs were fertilized, the embryo undergoes a great change of shape.
Page 323 - The digestive cavity now becomes greatly enlarged and cilia make their appearance upon its walls, the month becomes connected with the chamber which is thus formed and which becomes the stomach, and minute particles of food are drawn in by the cilia and can now be seen inside the stomach, where the vibration of the cilia keep them in constant motion. Up to this time the animal has developed without growing, and at the stage shown in plate vii, fig.
Page 324 - The narrow intestine is already partially coiled on itself, and this is the only departure from perfect bilateral symmetry in the whole body of the animal. The alimentary canal is lined throughout with ciliated cells, and the vibration of these cilia is the means by which the minute bodies which serve the larva for food are drawn into the digestive cavity. There are two pairs of delicate longitudinal muscles...
Page 324 - ... dense and nacreous. In the larva there is no such distinction, and the whole shell consists of a glassy substance devoid of any definite structure. The hinge line answers, as in the adult, to the dorsal side of the body. On the opposite or ventral side the wide mouth m and the minute vent i7 are seen at no great distance from one another. Projecting...
Page 323 - ... along a short area, the area of the hinge, upon the dorsal surface, where the two valves are in contact. "The two shells continue to grow at their edges, and soon become large enough to cover up and project a little beyond the surface of the body, as shown in Fig.
Page 324 - But these valves are symmetrical and similar in size and shape, so that the shell resembles that of a cockle more than it does that of an adult oyster. In the adult the shell is composed of two substances •Report Maryland Fish Commission, Annapolis, 1880, pp.
Page 323 - Fig. 45 it is seen in surface view, drawn in between the shells, and with its cilia folded down and at rest, as they are seen when the little oyster lies upon the bottom.
Page 319 - ... particles of organized matter. Ordinary sea water contains an abundance of this sort of food, which is drawn into the gills with the water, but as the water strains through the pores into the water tubes, the food particles are caught on the surface of the gills by a layer of adhesive slime which covers all the soft parts of the body. As soon as they are entangled the cilia strike against them in such a way as to roll or slide them along the gills towards the mouth.
Page 320 - I fell into an error in supposing that this style was lodged in a special pouch or sac, as described in my report to the Maryland commissioner in 1880. The "crystalline style" really lies in the first portion of the intestine and extends from the pyloric end of the stomach to the first bend of the intestine, where there is a marked constriction of the alimentary canal. It appears, therefore, to be a sort of loose valve in the cavity of the gut; its function may be to prevent coarse particles of food...
Page 317 - ... which passes from one shell to another and pulls them together. As soon as this muscle is cut the valves separate a little, and the right valve may be raised up and broken off from the left, thus exposing the right side of the body. The surface of the body is covered by the mantle, a thin...