“…Slower development of spontaneous activity and exploratory behaviors, as evidenced by the LL group and to a lesser extent by the SL group, has previously been observed (FraGkovi, 1968;Simonson, Yu, Anilane, Sherwin, & Chow, 1967;Simonson, Sherwin, Anilane, Yu, & Chow, 1969). Also, the LL pups showed a peculiar stiff-legged "hobble-skirt" gait and buckling movements of the hind-quarters attributable to possible abnormalities in bone structure (Platt, Heard, & Stewart, 1964).…”