We examined joint patterns of variation among eleven morphological variables, one meristic variable (vertebral count), and a genetic variable (DNA sequence variation in the mitochondria) cytochrome b gene) among juvenile (0-group) cod from the northeast Newfoundland shelf and the Grand Banks. Canonical discriminant analysis shows that the group centroids of fish on and off the Grand Banks are significantly different, and that fish from the most southerly region (30) have a significantly smaller

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... mean vertebral count than fish from the more northerly regions (3K, 3L). However, there is substantial overlap of individuals in canonical variate space and reclassification of fish into their, region of origin is successful in less than 50% of cases. Analysis of the distribution of ten DNA sequence genotypes indicates substantial hoMogeneity of genotypes within localities and little or no genetic subdivision among regions. The pattern of genetic differentiation is consistent with a model of recent origin of most genetic variation following a bottleneck in population numbers. The combination of morphological, meristic, and genetic analysis of Juvenile cod in NAFO Division 3K, 3L, and 30 does not support the hypothesis of stock separation among these areas. In particular, our data do not support the use of vertebral counts to define stock separation during early life history. Morphometric characters. Specimens were thawed for 3 hours to ensure uniform condition. Each individual was blotted dry and placed on a flat surface. Data included standard length, distance from snout to the anus, distance from snout to the origin of the third dorsal fin, distance from snout to the origin of the first dorsal fin, distance from snout to the origin of the pelvic fin, length of the head, eye diameter, snout length, jaw length, depth of head and depth of caudal peduncle (Figure 2) , measured to three significant digits with electronic callipers accurate to 0.01 mm.