explanation of Catholic progress in America. If we study with a little attention the extent to which immigration has influenced the development of the whole population of the country, and the exact proportion of the Catholic part of this immigration, we shall find confirmation of the conclusions to which we have been led by the simple testimony of figures. Immigration has never furnished more than six or seven per cent. of the decennial increase of the population of the United States, the growth of which has been at the rate of thirty-five per cent, during the same period. Immigration, therefore, contributed to it only one-fifth. Again, of these immigrants, including both Irish and Germans, not more than one-third have been Catholics. Moreover, we must take account of the considerable number of members that the Church has lost in the course of their dispersion all over the country. Clearly, then, the influence of immigration is not enough to account for the rapid progress of the faith. A careful analysis of the Catholic population at different tunes, and in different places, enables us to specify two other causes. 1. The Catholics are principally distributed at the North among the free states, where the population increases much faster than it does at the South; and the Catholic families, it has been observed, multiply much faster than the others, in consequence, no doubt, of their more active and regular habits of life, sustained morality, respect for the marriage tie, and regard for domestic obligations. This difference in fecundity is quite perceptible wherever the Catholic element {14} is strong--as in Canada, and the states of New York, Pennsylvania, Ohio, Michigan, Illinois, Wisconsin, etc., and, among the Southern states, in Louisiana, Maryland, and Missouri.