. 50- 40- 30- 20- 10 0 MUNIDA GREGARIA SEPT OCT NOV DEC JAN FEB MAR APR MAY Fig. I. Percentage of berried females to total catch of females in Munida subrugosa and M. gregaria. Berried females again appear in the January and February catches in increasing numbers, but a fall occurs in March and April. It seems probable that females are again beginning to bear eggs after spawning in September and October, but that the hauls made in March and April, in which the catches of M. gregaria were only small, have failed to sample this part of the population. Should spawning take place in September and
. 50- 40- 30- 20- 10 0 MUNIDA GREGARIA SEPT OCT NOV DEC JAN FEB MAR APR MAY Fig. I. Percentage of berried females to total catch of females in Munida subrugosa and M. gregaria. Berried females again appear in the January and February catches in increasing numbers, but a fall occurs in March and April. It seems probable that females are again beginning to bear eggs after spawning in September and October, but that the hauls made in March and April, in which the catches of M. gregaria were only small, have failed to sample this part of the population. Should spawning take place in September and October—which seems certain—and should eggs be extruded on to the pleopods in January and February—which seems probable—a period of eight months must be assigned to egg-carrying on the part of the female, a length of time which may be compared with ten months in the case of the American lobster, Homanis americamis (), Herrick (1895). In these circumstances, unless several months or a whole year are passed without breeding, the adult female can seldom, if ever, undergo more than one moult per year, the moult taking place between the time of hatching of the eggs and the resumption of egg bearing, October to January. The probability that long resting periods elapse between successive reproductive phases in the individual is upheld by the low per- centage of berried females to the total population at any time. Such resting periods
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectscientificexpedition
