This winter, notwithstanding the limitations imposed upon his work by the state of his health, was a very happy one to Agassiz. As mentioned in the above letter his wife and daughters had accompanied him to Charleston, and were established there in lodgings. Their holidays and occasional vacations were passed at the house of Dr. John E. Holbrook (the "Hollow Tree"), an exquisitely pretty and picturesque country place in the neighborhood of Charleston. Here Agassiz had been received almost as one of the family on his first visit to Charleston, shortly after his arrival in the United States. Dr. Holbrook's name, as the author of the "Herpetology of South Carolina," had long been familiar to him, and he now found a congenial and affectionate friend in the colleague and fellow-worker, whose personal acquaintance he had been anxious to make. Dr. Holbrook's wife, a direct descendant of John Rutledge of our revolutionary history, not only shared her husband's intellectual life, but had herself rare mental qualities, which had been developed by an unusually complete and efficient education. The wide and various range of her reading, the accuracy of her knowledge in matters of history and literature, and the charm of her conversation, made her a delightful companion. She exercised the most beneficent influence upon her large circle of young people, and without any effort to attract, she drew to herself whatever was most bright and clever in the society about her. The "Hollow Tree," presided over by its hospitable host and hostess was, therefore, the centre of a stimulating and cultivated social intercourse, free from all gene or formality. Here Agassiz and his family spent many happy days during their southern sojourn of 1852. The woods were yellow with jessamine, and the low, deep piazza was shut in by vines and roses; the open windows and the soft air full of sweet, out-of-door fragrance made one forget, spite of the wood fire on the hearth, that it was winter by the calendar. The days, passed almost wholly in the woods or on the veranda, closed with evenings spent not infrequently in discussions upon the scientific ideas and theories of the day, carried often beyond the region of demonstrated facts into that of speculative thought. An ever-recurring topic was that of the origin of the human race. It was Agassiz's declared belief that man had sprung not from a common stock, but from various centres, and that the original circumscription of these primordial groups of the human family corresponded in a large and general way with the distribution of animals and their combination into faunae. * (* See "Sketch of the Natural Provinces of the Animal World and their Relation to the Different Types of Man" included in Nott & Gliddon's "Types of Mankind".) His special zoological studies were too engrossing to allow him to follow this line of investigation closely, but it was never absent from his view of the animal kingdom as a whole. He valued extremely Mrs.