With them copulation normally takes place on dry land. The male extricates from the female the string of eggs, winds it round his hind legs and carries it about until the eggs are ready. Then, and not till then, he enters the water where the larvæ escape. If, however, one keeps these toads in a high temperature (25-30 C.) they enter the water to cool themselves and abandon their normal way of manipulating their brood because the string of spawn swells in water and does not remain sufficiently sticky to allow the male to fasten it to his thighs. The animals become gradually accustomed to live in water, and continue to carry on the business of reproduction there, even when the temperature is normal. As soon as the new instinct has become sufficiently established with the parents they beget offspring, which at a normal temperature go of their own accord into water to deposit their eggs, and also produce eggs more numerous than, and somewhat different from, those of the normal toad. Further, the males of this succeeding generation develop thumbs and forearms of a character which enables them to perform the difficult task of holding the females during copulation in the water. [Sidenote: C 5 & 6] The likeness of offspring to their parents is extremely great and goes into many details; this we frequently overlook because a divergence strikes us more than a similarity. A similarity becomes striking when it is a question of familiar peculiarities. These often relate to exterior unimportant peculiarities. Our collection contains +a pedigree+ (taken by Dr. Walter Bell from Bateson's "Mendel's Principles of Heredity"), Figure C 5, +of a family with peculiarly curled hair+; also in Figure C 6, a +case of heredity of a lock of white hair+, likewise taken from Bateson's work by Rizzoli. [Sidenote: C 7] The heredity of physical qualities is strikingly illustrated in Weinberg's Table C 7, showing the age +at death of the parents and the marital gross and nett fertility+. It is founded on the Stuttgart family registers, and comprises about 1,900 non-tubercular and about 3,000 tubercular families ("Archiv für Rassen and Gesellschafts Biologie" and Württemberger Jahrbücher für Statistik und Landeskunde, 1911). W. Weinberg adds: [Illustration: Relation of Age at Death of Parents to Gross and Nett Fertility. (After Weinberg.) Age of parents. Men: Women: Years under 30 A 0.58 C 1.00 A 0.93 C 1.79 B 0.62 D 1.34 B 0.82 D 1.72 30-40 A 1.38 C 2.81 A 1.65 C 3.40 B 1.41 D 2.70 B 1.81 D 3.53 40-50 A 2.31 C 3.94 A 1.88 C 3.34 B 1.90 D 3.69 B 2.25 D 4.52 50-60 A 2.39 C 4.05 A 2.31 C 3.69 B 2.21 D 4.04 B 1.92 D 3.42 60-70 A 3.05 C 4.76 A 2.62 C 4.37 B 2.88 D 4.65 B 2.79 D 4.28