54 Appendices to Second Annual Report 



Dr Heincke gives the position of the pectoral and pelvic fins as being 

 the same in both sprat and herring. I have very many examples which 

 show that this statement is not generally applicable to the fish examined 

 by me. 



The following table gives the various measurements of only one of 

 these : — 



Table showing Position and Length of Fins, &c, in a Sprat and Young 

 Herring of 118 mm. in Length. 



Length from tip of closed lower jaw to its articula- 

 tion, ...... 



Length from tip of closed lower jaw to back of head 

 (dorsal surface), ..... 



Length from tip of closed lower jaw to origin of 

 pectoral fin, 



Length from tip of closed lower jaw to first ray of 

 dorsal fin, 



Length from tip of closed lower jaw to origin of 

 pelvic fin, ..... 



Length from tip of closed lower jaw to first ray of 

 anal fin, ...... 



Length from tip of closed lower jaw to tip of longest 

 caudal ray, 



Length of base of dorsal fin, 



Length of base of anal fin, .... 



Sprat. 



8 mm. 



17 mm. 



21 '5 mm. 



55 mm. 



52 mm. 



75 mm. 



118 mm. 

 12 mm. 

 14 mm. 



Herring. 



10 - 5 mm. 

 19*5 mm. 



23 mm. 



53 mm. 

 57 '5 mm. 



76 mm. 



118 mm. 



12 mm. 

 11 "5 mm. 



The table shows that both the pectoral and pelvic fins were further 

 back in this small herring than in the sprat, and it shows that while the 

 dorsal fin of the sprat is behind the centre of the body, that of the herring 

 is exactly in the centre. Nearly all my other examples, however, show it 

 to be slightly posterior to the centre of the body in the herring, differing 

 from the position Dr Heincke found to obtain in his specimens, which 

 was in front of the centre. 



My specimens, again, did not show that the distance to the end of the 

 branchiostegal membrane is always greater in the sprat than in the her- 

 ring ; but the reverse occurred. So also with respect to a point which 

 Dr Heincke considers very characteristic, viz., that a line drawn from the 

 pectoral fin through the anterior lowest point of the operculum passes 

 below the eye of the sprat, but above generally in the herring. I find, 

 on the other hand, that this is an uncertain characteristic. The line 

 generally runs below the eye in the sprat and above it in the herring, 

 but among several herring 215 mm. (8 J inches) in length, as well as 

 among small fish, I found some in which this line passed through the 

 eye, some slightly above it, and some below. 



Internal Structures. — The same superiority, so far as number is 

 concerned, which is generally shown in the fin rays, scales, &c, of the 

 herring over those of the sprat, is seen again in a comparison of the other 

 organs. The vertebrae number 48 in the sprat (I found one exception, 

 that of a sprat with 47) and .56 in the herring, but, length for length, 

 those in the sprat are rather stouter than those of the herring. As 

 Wilson (loc. tit.) shows, the ribs are more numerous in the herring than 

 in the sprat. 



The gill rakers and filaments show the same difference. In the herring 



