70 



8. Gadus minutas 0. F. Müll., Poor Cod (Chart V) 



§ 1. Remarks on the identification 



Keferring to what has been said under Gadus Esmarki I need only repeat here that 

 it is often very difficult, even impossible, to separate the pelagic fry of the two species by 

 means of the external characters. We possess however in the number of vertebrae, after 

 clearing in xylol or the like, a certain if somewhat more troublesome means of disting- 

 uishing them. The accompanying table shows the number of vertebrae found in a con- 

 siderable number of adult specimens. The numbers for Scotland are from the already cited 

 work of H. C. Williamson, whilst those for the Skager Rak have been kindly placed at my 

 disposal by my colleague Dr. A. C. Johansen. The material from the Channel has been ob- 

 tained partly from the hauls of the "Thor", partly through the Marine Laboratory at 

 Plymouth. The counting of the vertebrae in these has been carried out respectively by 

 Stud. H. Blegvad and Cand. A. Stmbberg. 



Number of vertebrae in adult Gadus minutus 



No. of vertebrae Channel Scotland Skager Eak Total 



14 + 33 . . 1 1 



14 + 34 2 . . 1 3 



14 + 35 . . 1 1 



15 + 33 2 1 11 14 



15 + 34 15 3 23 41 



15 + 35 4 . . 21 25 



15 + 36 1 . . 1 2 



16 + 32 10 . . 10 



16 + 33 1 20 2 23 



16 + 34 10 8 18 



16 + 35 2 2 4 



17 + 32 3 . . 3 



17 + 33 3 . . 3 



17 + 34 ] . . 1 



Summary 



Total No. vertebrae Channel Scotland Skager Eak Total 



47 .. 1 1 



48 4 11 12 27 



49 ,16 26 26 68 



50 4 13 29 46 



51 1 3 3 7 



We see from this table that the total number of vertebrae in Gadus minutus varies 

 from 47 to 51 and the three most frequent numbers are 48, 49 and 50, whilst as has 

 been shown Gadus Esmarki has from 52 to 55 (most frequently 53 and 54). In this we 

 thus have a sure method of distinguishing the two species, and in most cases, as men- 

 tioned under G. Esmarki, it will be sufficient to count only the abdominal vertebrae, since 



