186 



Racial Studies in Fishes 



This detailed investigation thus quite confirms the results of my 

 previous investigations (see this Journal, Vol. vii, 1918, p. Ill) and 

 shows strikingly in all details how the average number of vertebrae 



Fig. 1. Average number of vertebrae in 11 Zoarces populations from the Ise Fjord — 



Roskilde Fjord area, Sealand, Denmark. 



The figures at the black spots indicate station numbers, those within the rectangles 



the average number of vertebrae of the population concerned. 



decreases from the coast and the mouth of the fjord towards the base of 

 the fjord. Here Zoarces has a short and plump shape, while the popu- 

 lations living farther out consist of individuals slender and elongated in 



