48 INLAND FISHERIES. 



1. When is the hr ceding -season of the scailoj) f — In order to make 

 sure of tlie time of breeding, the scallops of the set of 1899 (the 

 only set then present at AVickford) were examined at intervals 

 throug-h the winter and spring of 1900, and the condition of the 

 developing eggs and spermatozoa were observed. By the middle 

 of May all the specimens were apparently nearly ready to spawn. 



On the 8th of June several specimens which were being kept in 

 aquaria at the house-boat extruded their eggs in great quantities, 

 and from this time until July they continued to spawn. It is 

 difficult to fix the exact limits of the breeding-season, but it be- 

 gins about the first of June and reaches its height about the 

 middle of the month. In July nearly all the specimens had dis- 

 charged their eggs. 



It would be a fair statement to say that the scallops spawn in 

 June. 



2. What are the Ijreedhig -habits ? — The scallop differs in one 

 striking particular from our other edible shell-fish, the clam and the 

 oyster. It is an hermai^hrodite, the eggs and spermatozoa being 

 developed in the same individual, while in the clam and oyster the 

 sexes are separate. If the scallop be opened in May, when it is 

 sexually ripe, a bright orange-colored mass will be observed ; this 

 is made up of an immense number of eggs packed closely together. 

 The spermatozoa lie in a whitish mass near this place, but do not 

 occupy so much space. The eggs are extruded into the water as 

 in the case of the clam and oyster, there to be fertilized by sperm, 

 for the most part probably from other individuals. However, in 

 the aquarium on some occasions, when a single specimen was 

 kept by itself, eggs were laid and fertilized by the sperm of the 

 same individual. A few of them developed for a time, but not so 

 well as in other cases ; whether this was due to the self-fertilization 

 or not is a question not definitely settled. 



By watching the spawning of the animals it was observed that 

 they extruded their eggs, not little by little through several days, 

 but the whole mass, probably more than a million in number, were 

 discharged in the course of an hour and a half. 



