While this prevalence of the practise of collaboration in periods of dramatic productivity is significant, it is equally significant that there is no corresponding prevalence of the practise of collaboration in novel-writing. True it is that there are certain fairly well-known partnerships in the history of prose fiction--that of Erckmann-Chatrain, in French, for instance, and that of Besant and Rice in English. True it is that Dickens and Wilkie Collins were joint authors of 'No Thorofare,' and that Mark Twain and Charles Dudley Warner were joint authors of the 'Gilded Age.' True it is also, that novels have been written not only by two partners, but by what can fairly be described as a syndicate of associated authors, the 'King's Men' by four, 'Six of One and Half a Dozen of the Other' by six, and the 'Whole Family' by twelve (including Mr. Howells and Mr. Henry James, Mrs. Mary E. Wilkins Freeman, and Doctor Henry van Dyke). These freakish conglomerates are sporadic only; they seem to be little better than literary "stunts"; and even the union of two writers in the production of a single novel is far less frequently to be observed than the union of two writers in the production of a single play. The former is unusual, whereas the latter seems to be so common as to excite no comment. Now, there must be a reason for this difference. If the playwrights find it advantageous to double up, and the novelists do not discover any profit in putting on double harness, there ought to be some evident explanation. When we consider more carefully the essentially different conditions of the art of prose fiction and the art of play-writing, it is not difficult to perceive fairly obvious reasons for the varying procedure of the practitioners of these rival arts, which may seem so much alike, but which are really so very different in their methods and in their possibilities.