It is these frequent Exploring Expeditions of America that have done so much to enrich science in all its branches; as to them are appointed efficient geologists, botanists, naturalists, and other scientists, who send in their ‘Reports’ to Government, to be soon reproduced in the form of large, handsomely-illustrated volumes. Copies of these (often consisting of ten to eighteen thick quartos) are presented to the members of Congress, governors of States, and to many others in office, also to literary institutions. You may have access to them in almost every large town in America; and there is no information connected with the history and natural productions of the nation (including the aborigines) that cannot be found in their pages. And as our Transatlantic cousins are always exploring some new territory, and have still untold square miles of mountain and valley to explore, their scientific ‘Reports’ in huge quarto tomes can be more easily imagined than counted. This little digression from the viperine fangs is by way of introducing Dr. Elliot Coues. The volume in question was not forthcoming at the British Museum, therefore I ventured to trouble Professor Duncan with some inquiries, which were kindly responded to by the sight of the work itself. There is in Dr. Coues’ paper a good deal of what has been here already described; but there is also so much that is of additional interest, that for the benefit of those students who are not within reach of the British Museum (where, no doubt, the fast arriving quartos will get catalogued in due time), I will transcribe from the text some of the passages as relating to viperine fangs generally.