REPORT OF COMMISSIONERS OF INLAND FISHERIES. 31 



shows that the clams were read}^ to breed during the Last of May. 

 The spawning season, however, apparently reaches its height about 

 the middle of June, and clams examined after this time are found, 

 in most cases^ to have extruded their eggs ; by the first of July the 

 set on the shore is excellent. 



There is no doubt, however, that the clam also spawns to some 

 extent throughout the summer and probably until late autumn. 

 This has been proved by the discovery of the very small clams along 

 the shores and in the spat collectors at different times of the year. 

 » The clam is not unique in this respect, for many other species, 

 which have a regular breeding season, are known to spawn to a 

 greater or less extent at all times of the year. 



In the early spring of 1901, 1902, and 1903 there were discovered 

 sets of clams less than one-cpiarter of an inch long, which were dis- 

 tinguished from those of the summer sets by having the umbone (that 

 portion of the shell nearest the hinge) raised in relief from the rest 

 of the shell, and showing by its corrosion that the clams had lain 

 for months (i. e. during the winter) with almost no growth. The 

 small size of the clams during this dormant period, as indicated by 

 the corroded part of the shell, was ample proof that they could not 

 possibly have set during the previous summer; for the clams of the 

 previous summer's set averaged 25 mm. (1 inch) in length at the 

 commencement of winter. Throughout the summer the clams of 

 the fall set were readily distinguished from those which set in the 

 spring. Along the shore, this fall's set would scarcely be noticeable, 

 but in the commission's spat collector at Rumstick there were, in 

 the middle of Januarj^, 1903, more than one hundred to the square 

 foot. At Kickemuit river, in a spot very favorable for clams, there 

 were at this time hardly more than two or three to the square foot. 

 According to the observations of the last five years the clams which 

 set at any time other than the early summer seem to be of little 

 economic importance. 



