Between the years 1880 and 1883 several papers on mammalian zoology were published by Flower in the _Proceedings_ of the Zoological Society and elsewhere, none of which can be regarded as of first-rate importance. The first of these (_P.Z.S._ 1880) dealt with the internal anatomy of that rare mammal, the bush-dog (_Speothus_, or _Icticyon_, _venaticus_), of Guiana, which had never previously been described. The author regarded this animal as a specialised member of the Canidæ, showing some signs of affinity with the wild dogs (_Cyon_) of Asia. In 1880 the museum of the Royal College of Surgeons received a very large skull of the elephant-seal or sea-elephant (_Macrorhinus leoninus_); and this induced Flower to draw up some notes on that enormous creature, which appeared in the above-named journal for 1881. The author described it as “an animal which, notwithstanding its former abundance and wide distribution, and its great zoological interest, is still very imperfectly known anatomically, and very poorly represented in collections.” Fortunately, since that date—mainly owing to the energy and liberality of Mr. Rothschild—specimens of the skin and skeleton of this huge seal have been secured for our museums before it was too late. In the same volume Flower drew attention to the evidence showing that the sea-cow, or manati, of which a pair were living at the time in the Brighton Aquarium, occasionally, or periodically, comes ashore for the purpose of grazing. In the same year appeared an article from his pen in the _British Medical Journal_ on the anatomy of the Cetacea and Edentata; while in 1882 the question of the mutual relationships of the mammals commonly included in the latter order (such as sloths, ant-eaters, armadillos, pangolins, and aard-varks) were discussed by him in the _Proceedings_ of the Zoological Society. The trend of the paper last mentioned, as well as that of some of his other communications published shortly before, indicates that about this time, instead of restricting his attention more or less entirely to their anatomy, Flower was much occupied with the subject of the classification of the Mammalia. And the reason is not far to seek, for he had undertaken not only the volume of the “Catalogue of Osteological Specimens in the Museum of the Royal College of Surgeons,” dealing with mammals other than man, but he had likewise engaged (in co-operation with the late Dr. Dobson) to write the article “Mammalia” for the ninth edition of the _Encyclopædia Britannica_. With the view apparently of clearing the way for these two important contributions to zoology, he published during the early part of 1883 in the Zoological Society’s _Proceedings_ a paper on the “Arrangement of the Orders and Families of Mammalia.”