76 



Appendices to Fourth Annual Report 



reason for doing so except in so far as the question is often asked, 

 Below what length is a herring a matie ? If the correct meaning of 

 immature is strictly applied to the matie, the size given above for these 

 would fairly ansvi^er the question ; but, if the matie is to be considered 

 simply as a young herring, irrespective of its sexual condition, perhaps 

 spawning — but not yet being fully grown — we could scarcely be safe in 

 putting its length higher than 205 or 210 mm., which is considerably 

 below what is often called a matie at present. Of the herring sent up 

 from the various districts for this investigation, 12 per cent, of those 

 in a sexually mature condition, i.e., more or less ripe or spent, were under 

 210 mm. long to end of scales, and 230 mm. to tip of tail. 



In considering the size of the herring there is another measurement 

 than that of length which has to be taken into account, that is, the depth 

 and girth of the fish. Without going into detail, it may be said that the 

 depth of the mature herring caught during or near to the time of spawn- 

 ing is almost wholly influenced in its extent by the condition of the 

 reproductive organs; and so many variable degrees of these are found 

 that any measurement of the depth of the body proper is most unsatis- 

 factory as a test of the size of the fish, and only of interest in connection 

 with the amount of development of the roe or milt. 



There is, however, a point which gives a fair index of the size of the 

 fish in this respect, and which is but very little affected by the size of the 

 generative organs. This is the depth of the fish at the anterior end of 

 the body, in a line with the back of the head, the upper point being 

 fixed by the dorsal surface of the supra-occipital bone, the lower by the 

 ventral edges of the clavicles of the shoulder girdle. Posterior to this, 

 even so little as in a line with the back of the operculum, the measure- 

 ment is so variable as to be untrustworthy. 



Table V. gives the result of the measurements made of the depth of the 

 herring at this point. For reasons which will afterwards appear, the 

 depth is taken in parts of the length of the body only, i.e., the varying 

 lengths of the head and tail are excluded. The body depth at the part 

 referred to does not vary much in the mature fish, the extremes being 

 •18 and '23 of the length of the body, found in fish measuring 214 mm. 

 and 254 mm. in length of body respectively, these examples giving 

 a depth of from '12 to '17 of the total length to the tip of caudal fin. 

 Among the immature fish it varies from '17 to '23, found in fish measur- 

 ing 180 mm. and 190 mm. in length of body respectively ; that is to say, 

 among the immature fish the depth of body has a range of variation, and 

 holds a proportion to the length almost identical with that of the mature. 

 If, for convenience, the amount of this variation be formed into five equal 

 divisions, we find the percentage of fish included in each to be as follows : — 



TABLE (V.) of Herrings arranged according to depth of body. 



Katio of depth to 

 length of body 

 (minus head 

 and tail). 



•170 

 to 

 •180 



•181 

 to 

 •192 



•193 



to 

 •204 



•205 

 to 

 •216 



•217 



to 

 •228 



o 



& ( Mature. 

 1 ) 



1-4 



24-5 



39-6 



27^0 



7.4 



g ( Immature. 



12-2 



36^6 



20^7 



18^3 



12^2 















