After the death of Edward Forbes, Dr. Cobbold resigned his appointments in Edinburgh, and became Lecturer on Botany at St. Mary’s Hospital. Two years later he transferred his services to the Middlesex Hospital, lecturing there for thirteen years on Zoology and Comparative Anatomy. During his connection with the Middlesex Hospital he took up the branch of zoology and medicine with which his name will be most distinctively associated. During three successive years he examined the bodies of animals dying at the Zoological Gardens, especially with a view to discovering the presence of parasitic worms in them. Many papers were contributed by him to the Linnean and Zoological Transactions and Proceedings, among which we may call attention to “Remarks on all the Human Entozoa” (Zool. Soc. Proc., 1862). In 1864 Dr. Cobbold was elected F.R.S., and in the same year published his “Introductory Treatise on the Entozoa,” which established his reputation, the _Lancet_ declaring that it formed a noble contribution to medical science and a credit to our national literature. Up to the year 1865 Dr. Cobbold persevered in the pursuit of pure science, refusing all inducements to practice; but finding that after his twenty years of zealous labour, no suitable scientific post opened for him, he at length commenced practice in Wimpole Street, removing later to Harley Street. Here his great knowledge of the habits and treatment of internal worm parasites became available for professional purposes, and his services were largely sought. But scientific pursuits and public lecturing still claimed his attention, and among the achievements of his later years are his book on Tapeworms, which has gone through several editions; his lectures on practical helminthology, entitled “Worms;” a manual of the “Parasites of the Domesticated Animals,” a larger treatise on Parasites, a smaller supplementary work on Human Parasites. In 1873 Dr. Cobbold received the appointment of Professor of Botany at the Royal Veterinary College, and soon afterwards a special chair of helminthology was established for him at the College, for giving instruction on the parasites and parasitic diseases of domesticated animals to veterinary students. In connection with this work. Dr. Cobbold went still more deeply into the parasitic diseases of domestic animals, such as those which caused grouse disease, ostrich and pigeon epidemics, gapes in chickens, &c. He delivered a course of lectures on the “Parasites of Animals employed as Food” at the Society of Arts. He has been the first to describe many new species of internal worms from elephants, horses, cattle, sheep, and dogs. One of the most elaborate of his special memoirs is that in which he has described the parasites of elephants, in the Linnean Society’s Transactions. With these extensive researches in comparative anatomy, Dr. Cobbold has not neglected human parasites of late years, and