52 EEPORT OF COMMISSIONERS OF INLAND FISHERIES. 



Another attempt to get at the breeding season of the quahaug 

 was made by an indirect route. As soon as the collecting of qua- 

 haugs in the prolific area at Wickford began, it was noticed that, 

 though the animals were apparently just as numerous at one time 

 as another, their sizes varied little. There was not the increase in 

 size that one would expect if the quahaugs have a short and defi- 

 nite breeding season. There were just as many small quahaugs 

 found at the end of September as at the beginning of the month ; 

 and, in fact, the catch in January from the same place showed 

 that there were as many small animals as in the previous Septem- 

 ber. (Fig 19). At first it would seem that this similarity in size 

 means that the quahaugs are breeding throughout the year, a sup- 

 position that other evidence contradicts rather than substantiates. 



It is possible, and even probable, that the j^oung fry of the qua- 

 haug behave like those of the clam ; that they " set" upon coming 

 in contact with sticks, stones, eel-grass, and other hard objects 

 along shore. Here again the data is, as yet, insufficient to war- 

 rant a conclusion. It is true that, as a general rule, more quahaugs 

 of the smallest sizes so far obtainable are to be found in the eel- 

 grass; but this does not necessarily mean that the quahaugs 

 "set" here and attain a certain size before they venture beyond 

 the confines of the eel-grass. Unlike the clam, the quahaug is an 

 animal that possesses the power of locomotion to a comparatively 

 high degree; aud it may "set" almost anywhere on shore, and 

 then make its way into the eel-grass. This is a point that remains 

 to be determined. 



Hate of Growth. — The measurements used in determining rate 

 of growth in the quahaug are the following : 



1. — The dimension from the hinge to the free edge of the valve, 

 or the dors* (-ventral diameter. 

 2. — The long diameter. 

 3. — The thickness of the animal, or the lateral diameter. 



_ On August 20th six quahaugs were measured, marked, and re- 

 planted. Their dimensions on this date, on September 5th, 



