THE determination of intraspecific races among clupeoid fishes is an important problem that has long challenged fisheries workers. Many workers have attempted such determinations in the past on the basis of various meristic characters; but although a number of characters have been shown to vary, the number of vertebrae has been used more consistently than any other and is the most generally accepted criterion (cf. Runnstr6m, 1941: 5). Investigators working on the shad [Alosa sapidissima (Wilson) ] from the Connecticut River are confronted with the same general problem. Are the fish of that stream distinct from those of other streams of the North Atlantic seaboard, and, if so, can the differences be revealed by vertebral counts? These notes are published with two thoughts in mind: (1) to make such data as are here presented available to other workers, and (2) to point out some difficulties that have arisen. Vladykov and Wallace (1937) studied collections of shad from three separate localities on the western coast of the North Atlantic from the viewpoint of this general problem. Their samples were from the Schubenacadie River in Nova Scotia and from the Delaware and Chesapeake bays. In addition to analyzing data that they themselves collected, they compared their results with those previously reported by Leim (1924) from the Schubenacadie River, as well as from Scotsman Bay in Nova Scotia. On the basis of such meristic features as the number of vertebrae, pectoral fin rays and ventral scutes, Vladykov and Wallace indicated that there were significantly distinct races of shad between the Nova Scotia areas and the Chesapeake Bay. These latter differences, they maintained, were somewhat substantiated by such factors as the composition of the spawning population and by differences in the length of the fish. Recently the Bingham Oceanographic Laboratory,1 in co-operation with the Connecticut State Board of Fisheries and Game, assembled data on the vertebrae of shad that entered the Connecticut River in 1945 and 1946 as one phase of a larger program of research on the species.