Mean numbers of vertebral centra in Clupea pallasi decrease from n. to s. This decrease is confined almost entirely to the precaudal section of the backbone. In some regions, e.g. contiguous waters of British Columbia and Washington, certain populations depart widely in mean numbers of vertebrae from the values usually found in the area. No sexual dimorphism has been found in mean numbers of vertebrae or other meristic characters. No regular clines in mean numbers of dorsal rays or gillrakers have been found, but the mean numbers of anal and pectoral rays decrease from north to south. Mean numbers of ventral scutes also tend to decrease with latitude, although the highest mean value was found in herring from San Diego Bay. In herring of equivalent size or age, females from northern waters produce more eggs. Two points of difference between C. pallasi and C. harengus, the depth of spawning and the mean number of pectoral rays, appear to be less distinct than formerly supposed.