The results of 9 expts. in which cutaneous infection with the cattle hook-worm was demonstrated are recorded. Acute symptoms, loss in wt., and 1 death occurred between 30 and 60 days after inoculation. The 1st eggs appeared in the feces between the 52d and the 68th day after inoculation. The degree of infection as measured by egg counts was not correlated with the severity of the symptoms; animals with the highest egg counts had previously shown the slightest symptoms, while several of the animals with low or negative egg counts had shown severe symptoms.