59 



transversely in the body, its ends attached respectively 

 to the right and left valves. By the contraction and 

 relaxation of this muscle the shell is alternately closed 

 and opened. When disease attacks ii, its fibres waste, 

 the adhesion of the ends of the muscle to the inner face 

 of the valves is impaired and the insertion surface 

 becomes rough, irregular, and often quite tubercular. 

 Concurrently the muscle gradually loses its power to 

 sustain prolonged contraction, the shell gapes and in 

 this condition the oyster becomes an easy prey to pre- 

 daceous foes. If it does not perish thus, life gradually 

 ebbs away, the oyster dying from debility, the inability 

 of the organs to carry on their respective functions. 



The last disease of sufficient importance to warrant 

 notice is boudeuse, the virtual cessation of growth affect- 

 ing oysters en masse. It is a condition directly induced 

 by overcrowding in localities where the food supply is 

 not sufficiently superabundant as to sustain the rapidly 

 increasing demands made upon it by millions of young 

 oysters hastening to maturity. While the oysters are 

 quite small, their collective appetites may be adequately 

 satisfied but while the amount of food available may be 

 sufficient for a given quantity of one-year-olds, it may be 

 wholly inadequate for the same number at double that 

 age. Usually this disease does become apparent among 

 crowded oysters about the age of two years. The only 

 remedy is to reduce the numbers very greatly, but when 

 the ailment has affected the oysters for any considerable 

 period its stunting effect becomes established and even 

 when such oysters are transferred to parks where the 

 food supply is rich, they never develop into a really 

 satisfactory condition ; they retain their stunted appear- 

 ance more or less for the remainder of their existence. 



From this list of enemies and diseases whereby the 

 stock may be depleted one might infer that oyster 

 culture is surrounded by very serious risks. In practice 

 the careful parker has seldom to think seriously of more 

 than two or three of these inimical influences against 



