“Adding now to the 866 proglottides the thirty-four already eliminated, 900 would be the number of the segments; and reckoning the length of each of the latter to be fourteen millimètres, we should have had the _strobila_ (deprived of the head and neck) reaching a length of 4·75 mètres. Further, calculating the head and neck to be eight millimètres long, a total length of 4·83 mètres would be the result. “From all these facts we may conclude that the _Tænia_ has, in our instance, reached an approximative length of seventy-two millimètres a day, affording a daily production of 13·43 proglottides.” In relation to requirements of state medicine I have thought Perroncito’s researches sufficiently valuable to be quoted at some length; but their chief interest culminates in the worm-feeding experiments. Excellent in all respects as was the conduct of the medical students who, with Professor Perroncito’s approval, swallowed living specimens of the _Cysticercus bovis_, the intentional ingestion of beef measles is by no means a novelty. Eight or ten years back Dr Oliver (after explaining to one of the selected victims the possible consequences of the experiment) induced a Mahommedan syce or groom and a Hindoo boy to swallow perfectly fresh and living beef measles. In this way Dr Oliver successfully reared the _Tænia mediocanellata_ in India, and he was thus enabled to fix the amount of time necessary for the full growth of the strobila. Many other persons have displayed an equal amount of zeal in the cause of helminthology, by partaking of the larvæ or germs of other parasites. Thus, at the risk of repetition, I may state that Möller many years ago swallowed the slender-necked hydatid (_Cysticercus tenuicollis_) in the hope of infesting himself with _Tænia marginata_. Several persons have defiantly swallowed trichinised flesh. Professor Leuckart and some of his pupils also courageously swallowed the eggs of _Oxyurides_, and they had the infinite satisfaction of noticing the young worms in their fæcal discharges some fifteen days afterwards. Dr Crisp ate part of the cooked flesh of an animal that had died of cattle plague, and I myself partook of moderately cooked meat which I knew to be swarming with psorosperms. These obscure organisms were by some persons considered to be either a cause or product of the rinderpest. They will be noticed in my account of the Protozoal parasites.