198 Spawning Period of Mussels. 



more uniform scattering of eggs among the tissues of the 

 mantle, and these are of a ruddier orange tint. An appeal to 

 the microscope settles the difficulty. Thus it follows that the 

 common and the horse mussel are not hemaphrodite like our 

 native oyster, but rather resemble the Portuguese and the 

 American oyster in the sexes being separate. 



In our haphazard examination of a series of specimens of 

 the common mussel, the sexes seemed to be tolerably evenly 

 divided. Mclntosh inclines to think females preponderate. 

 But Jas. Johnstone* has shown, by a more extensive research 

 to determine this point on the Lancashire mussel beds, that 

 there the ratio of sex stands as six males to five females, or 

 thereabouts. 



The period in which mussels usually spawn in the Kent 

 and Essex waters is reckoned by the growers to be from spring 

 till midsummer. As in the case of the oyster, much depends on 

 weather conditions. There is no hard and fast date of their 

 commencing or ceasing to emit spawn. This appears to be the 

 case equally whether self-sown colonies or among those laid on 

 the beds under semi-cultivation. In cold and wet springs the 

 mussel men expect them to be later of breeding. Speaking in 

 a general way, with us April, May and June may be regarded 

 as when the great bulk of the mussels are " sick " and out of 

 order, and then their floating spat (i.e., stage, with ciliate 

 swimming fringe) is to be obtained in numbers in the tow-net 

 in the neighbourhood of the mussel and oyster beds. By the 

 close of June, even occasionally some weeks earlier, the growers 

 notice many mussels to be already spent or fast losing flesh. 

 By mid-July some are already steadily recovering from the 

 thinning effects of procreation, and begin " putting on flesh," 

 as the phrase goes. Meantime, and till August, there are still 

 a very few late breeders, but the great majority are fast 

 getting into sound condition, fit for market, that is if the 



* " The Spawning of the Mussel (Mytilus edulis)," Rep. Lane. Sea Fish. Labor, 

 for 1898 (1899). 



