R. batis L., R. nidrosiensis Collett and R. oxyrhynchus (L.) from Norwegian waters are described and depicted. According to Clark (192G) 12 body measurements are taken on each animal, and on the basis of these from 4 to 6 body indices are derived. The preparation and the structure of the crania are described. The crania are depicted and 10 cranium measurements are taken on the basis of which 5 cranium indices are computed.The results obtained by comparing the morphology, body measurements and body indices, the structure of the cranium, the cranium measurements and cranium indices of the three species, is that it is reasonable to assume that R. batis, R. nidrosiensis and R. oxyrhynchus are three subspecies of one single species, thus forming a “Rassenkreis”. |
