13 



be definitely stated it reaches the bottom. It may be said then 

 to be about 1 cm. in length. During its pelagic life the young 

 gurnard develops large pectoral fins which will enable it to some 

 extent to resist the current. But the conditions are such as to 

 cause a gathering on the bottom over a wide area, and varying in 

 depth, say, from about 5 to 30 fathoms of the products of a parti- 

 cular spawning ground (fig. 5). If we had the means to examine 

 such an area in the latter part of the year we should expect to get 

 a picture of the population of the young gurnards of the year which 

 would be very similar to that expressed in fig. 1 of this paper. 



These young gurnards would also be found to vary in size 

 because of the long spawning period, and probably they do not 

 move far if at all during the first winter. But in spring they migrate 

 inshore, and measure from 7 to 12 cm. (one year). At the end of 

 the summer they retreat into somewhat deeper water without as 

 a rule quitting the territorial region, and re-enter the bays along 

 the coast a second time when they measure 13 to 20 cm. (two 

 years). The succeeding winter migration cg-rries them still further 

 north and into deeper water, and on their return to the shore 

 they have attained a size of from 18 to 24 cm. (three years). It 

 is very probable that at the end of this season inshore the majority 

 of the males and some of the females become mature, and the 

 result will be to intensify the distance of the winter migration, 

 from which they will return to a spawning ground ; and from what 

 we know with regard to other species it may be said this need not 

 be the one from which they originated, but one still further to the 

 north (fig. 6). 



The life-history of the gurnard may be concluded therefore to 

 be : — 



1. — A denatant drift of a number of weeks in the egg and 

 larval stages, a gradual sinking in the water, and the coming to 

 rest in depths of from 5-30 fathoms, but for the most part in 10-25 

 fathoms. 



2. — Next spring a denatant migration inshore, and a concen- 

 tration of the products of the previous j^ear's spawning season. 



3. — A contranatant migration into deeper water again at the 

 end of the summer. 



4. — Thereafter a seasonal migration from deep water to shallow 

 water, and as in the previous cases the spring migration being from 



