EASTERN OYSTER CULTURE IN OREGON. 



= 35 



States Fish Commission during the summers of 1897 and 1898, 

 among other things resorted to the artificial fertilization of the 

 eggs in a temporary laboratory, carrying the delicate embryos 

 to the swimming stage and dumping them by thousands into the 

 bay. Given some clean crocks, a microscope, dissecting instru- 

 ments, tumblers, rubber tubing, tliermometers, and instruments 

 to test the saltness of the water, and innumerable embryos can be 

 cared for without much trouble. The process, as practiced by 

 Brooks, Ryder, ISTelson, and others in America, is too well known 

 to need repeating here. Its efficacy is well established, and, in 

 spite of the incredulity of the oystermen, who wished to see the 

 oysters spawn " spontaneous," as they expressed it, an incredulity 

 amounting almost to opposition, the writer has persevered in this 

 work for two seasons and intends to continue it the coming summer. 

 The native oyster of this Northwest coast (Ostrea lurida), small- 

 er and by many preferred to its Eastern congener, while it is far less 

 fruitful in its spawning than the latter, retains its young within the 

 parent shell until long after they have passed the tender stages, 

 when they leave the mantle cavity of the parent to swim for them- 

 selves. This oyster could rightly be called viviparous, while the 

 Eastern oyster is oviparous. On account of its nurse-acting pro- 



Ax ExrKlilMENTAL SPAWMNG FluAT. 



clivities this West-coast oyster has an immense advantage here over 

 the introduced species. The latter's eggs have to run the follow- 

 ing gantlet: (1) N^ot meeting with a fertilizing cell and perishing 

 in consequence; (2) sinking, before or after fertilization, in the 

 fatal mud; (3) being eaten by small fish and other minute animals; 



