OF MASSACHUSETTS. 49 



furrows are colorless. Yellow markings are found on these small scal- 

 lops below the hinge line in scattered patches about the umbo. 



Do Scallops change Color as they grow older? In 1906 the follow- 

 ing experiments were made: Scallops of the 1906 set, ranging from 

 10 to 20 millimeters, were obtained from Stage Harbor, Chatham. 

 These were sorted according to color and placed in wire baskets and 

 suspended from the raft at Monomoy Point. On Sept. 7, 1906, they 

 were put on the raft, and on Oct. 23, 1906, the color changes noted. 

 A similar experiment was made with smaller scallops, about 3 milli- 

 meters in size, from August 15 to September 15. 



These two observations indicate that there is a slight change in color 

 from white to medium and from medium to dark, or that the scallop 

 shell acquires as it grows older a darker shade. The dark scallops 

 always remain the same, while the light-colored ones gradually take 

 on a darker hue which never becomes very intense. Scallops between 

 3 and 12 millimeters vary in deepening their color, some requiring one 

 week, others three, before any appreciable change is noticeable. 



Is Color hereditary or due to the Environment? The color of the 

 shell seems to be an inherent quality and not influenced radically by 

 the environment. An orange-colored scallop is always orange color, 

 as has been shown by keeping record of the same colored scallops in 

 wire baskets, and a small orange-colored scallop will always remain 

 the same color, no matter how large it becomes. Color is not wholly 

 unaffected by environment, as modifying changes occur ; but in the main 

 it is a constant quantity. The nature of the surface to which the scal- 

 lops are attached does not seem to determine the color of the shell, as 

 on light-colored wooden boxes 150 out of 1,100 scallops were dark 

 colored, while the remainder of the scallops, which measured from 2 to 

 3 millimeters, were of a lighter hue. This shows that environment does 

 not regulate the color formation of the shell, as both dark and light 

 colored scallops are found on the same surface. It is perhaps worthy 

 of notice that the majority, 86 l /2 per cent., were light colored, while 

 the rest, only IS 1 /^ per cent., were dark. The conclusion is that environ- 

 ment, while perhaps tending to modify the coloration, does not deter- 

 mine the true color of the scallop, which is an inherent quality in the 

 animal. 



An interesting experiment could possibly be made in regard to color 

 inheritance if certain mechanical difficulties in the line of artificial 

 propagation could be overcome. It would be of scientific interest to 

 know whether scallops of a certain color would transmit this color to 

 their offspring, and if so in what proportions. To accomplish this it 

 would be necessary to have inclosed spawning ponds in which the 

 scallops of the required color could be separated from the rest. At 

 present, owing to the difficulties in the breeding of scallops, this is not 

 possible, and an experiment of this nature will have to be postponed 

 until artificial breeding is more fully perfected. 



