14 



be determined by the time elapsing between casting and the 

 hatching of the young, whereas, in males, casting may take 

 place annually or at less intervals. 



Norway Lobsters which are less than 11 cm. in length are 

 of little if any market value, and these are found to be only 

 about 6 per cent, of the number examined. The general opinion 

 amongst the fishermen is that most large prawns are caught 

 north of the Tyne, and that the smaller ones are most abundant 

 in the neighbourhood of Seaham. 



Proportion of Males, Females akd Berried Females. — 

 Table V. — Altogether 7,686 Norway lobsters have been xamined. 

 Of these, 73*5 per cent, were males, 26'5 per cent, weid females, 

 and the percentage of berried females in the total number of 

 females was 5'8. The percentages of females and berried 

 females are small when taken for the whole of the period during 

 which the observations have been made. But these percentages 

 are found to vary throughout the year, and although in no 

 month have the females been found to exceed the males in 

 number, yet during the winter months the number of females 

 increases and sometimes almost equals that of the males. At 

 this time the percentage of berried females is least. From 

 individuals kept in captivity it is clear that the eggs are earned 

 during the winter, and therefore the berried females exist 

 although not caught by the trawl. It is probable then that 

 the females may exceed the males in number, and that habits 

 of which no knowledge at present is obtainable bring about the 

 small percentages of females in summer and of berried females 

 in winter. 



Hatching and Period of Incubation. — Berried females have 

 been found with the young leaving the egg or nearly ready to 

 do so in the months May to September, the highest percentage 

 being in June. In July, August, September and October by 

 far the greater number of berried females carried recently 

 spawned eggs, the highest percentage being found in Sep- 

 tember. For particulars see Table V. If June and September 

 be taken as the chief months for hatching and spawning, the 

 period of incubation is probably about nine months. 



The eggs on being spawned are dark green in colour. Later 

 they change to a lighter green, and with the growth of the 



