Brown-Séquard noticed that almost all his animals in which the great sciatic was divided acquired the "epilepsy" and nibbled those parts of their feet in which sensation had been lost. Of the offspring of such animals he found that a very small proportion exhibited a malformation of the feet, and of these some showed the "epilepsy." The proportion which showed the "epilepsy" was one to two per cent. of the offspring. Morgan[11] is quoted by Graham Brown as having suggested that the loss of toes in the offspring may have been due to mutilation by the mother, following his experience in a case in which the tails of mice in succeeding litters were thus devoured, and there can be little doubt that in this suggestion lies the clue to the explanation of the whole mystery. Graham Brown concludes that it may be supposed with every degree of probability that the "transmission" was due to injuries inflicted upon the young by their parents. With this conclusion most people will now be disposed to agree, and we may hope that we shall hear the last of this curious myth--to the elucidation of which a vast quantity of research has been devoted. The series of experiments made by Kammerer with various Amphibia have attracted much attention and have been acclaimed by Semon and other believers in the transmission of acquired characters as giving proof of the truth of their views. With respect to these observations the chief comment to be made is that they are as yet unconfirmed. Many of the results that are described, it is scarcely necessary to say, will strike most readers as very improbable; but coming from a man of Dr. Kammerer's wide experience, and accepted as they are by Dr. Przibram, under whose auspices the work was done in the Biologische Vesuchsanstalt at Vienna, the published accounts are worthy of the most respectful attention. The evidence relates chiefly to three distinct groups of occurrences: 1. Modification in _Alytes obstetricans_, the Midwife Toad, affecting both the structure and the mode of reproduction, induced by compulsory change of habits. 2. Modification in the mode of reproduction of _Salamandra atra_ and _maculosa_ induced by compulsory change of habits. 3. Modification in the colour of _Salamandra maculosa_ induced by change in the colour of the soil on which the animals were kept. 1. I will take first the case of _Alytes_,[12] because it is the most definite example, and because it is the case which most readily admits of repetition and verification. The habits of _Alytes obstetricans_ are well known. The animals copulate on land. As the strings of eggs leave the female they are entangled by the hind legs of the male, and being adhesive they stick to him and undergo their development attached to his back and legs. The number of eggs varies from 18 to 86, a number much smaller than is usual in toads and frogs which lay their eggs in water. The eggs are large and full of yolk.