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Part III. — Eighteenth Annual Report 



have cast in September, and those found in December and January may 

 have cast in October. Of those got in July, August, and September, a 

 number in each month were observed to have " just cast." As for the 

 creel-caught crabs, comparatively few soft examples are got in July ; at 

 that time the few boats still engaged in the fishing are working close 

 inshore. In August a number of soft crabs are to be got in shallow 

 water along with the large dirty females, which show, by the presence 

 of the empty egg-capsules on their swimmerets, that they have recently 

 hatched their eggs. The soft crabs are then for the most part of small 

 size. For example, in a catch of 176 crabs on August 6th, 1899, of the 

 57 soft crabs 44 were between 3| and 5f inches, while 11 only were 

 above 5|- inches in size. These crabs were for the most part crabs which 

 had cast out of the immature group. When, however, the fishermen 

 begin in the latter half of September to shoot their creels two to three 

 miles offshore in over 20 fathoms water, they get immense numbers of 

 soft crabs over gauge size, and including at that time a considerable 

 proportion of very large crabs up to 7 inches. After September, with 

 each month there is a rapid reduction in the numbers of soft crabs over 

 4| inches in size, till in January they practically disappear from the 

 creels. In the case of the soft crabs under 4J inches, a larger number 

 are taken in the creels in October than in any other month. As will 

 be pointed out below, the small crabs appear to migrate to deep water 

 a little later in the year than the gauge crabs. The statistics of the 

 large crabs are probably therefore of more importance on the question 

 under discussion. Among the crabs 4| inches and over in breadth, the 

 percentage of soft crabs during the last four months of the year and 

 January were respectively : — September, 80 per cent. ; October, 55 per 

 cent. ; November, 42 per cent. ; December, 22 per cent. ; January, 2 per 

 cent. (Table XIII., p. 143). From the fact that after September the 

 numbers of large soft crabs decline rapidly, it is evident that there can be 

 in October no considerable accession, to the ranks of the soft crabs, of crabs 

 that cast in that month ; and similarly in the following months the number 

 of crabs which are, through becoming hard, being withdrawn from the 

 soft class is very much greater than the number of those which are 

 joining the same. A great number of crabs which are soft in September 

 are hard in October. There is good reason for allowing for the harden- 

 ing process during the winter months about 3| to 4 months ; it may be 

 taken for granted that the period will not be longer during the summer 

 months. Thus, the large number of crabs which became hard in 

 October very probably cast their shells some time in J uly ; then those 

 which cast in August and September should be hard again in November 

 and December respectively. From the great reduction in the number 

 of the soft crabs each month after September, it might be possible, 

 given the average time required for hardening, by counting backwards 

 to arrive at the month when the crabs just hardened had cast their 

 shells. From the facts already known, however, we can get at the main 

 casting period with fair accuracy, and this, there appears to be little 

 doubt, is a period of three months — July, August, and September. If 

 this is the case, we should expect to find the greatest number of soft 

 crabs in September, because during that month we should have the soft 

 crabs of the whole period. Those that cast in July and August would 

 in September be still soft ; in October the July crabs would become 

 hard ; in November the August casters would probably again be 

 marketable ; and so with the September crabs in December. After 

 December and until the following August the number of soft crabs is 

 practically negligeable. Wilson* says that casting goes on in July and 

 August. Bucklandt quotes the evidence of Mr. Hutton, Customs 



