446 THE ZOOLOGIST, 



the stimuli are applied for several spawning periods in succession 

 this method of reproduction becomes habitual in the individual, 

 and occurs without further stimulation. The larvae thus pro- 

 duced are coffee-brown or grey (instead of black), striped with 

 darker bands. Their movements are much more intelligent 

 than those of larvae at the same stage which have been cut out of 

 the uterus by an operation, and the gills become adapted for 

 aquatic respiration much more rapidly. Moreover, they at once 

 begin to feed on small aquatic animals. These larvae, when 

 they reach the sexually mature stage, in their turn produce 

 aquatic larval forms even in the first spawning period, and it is 

 found that the stimuli necessary to produce this result need not 

 be so large in amount as was the case in their parents. 



Exactly similar results are obtained with the young produced 

 in the adult stage by S. maculosa. At the first spawning period 

 they only produce one young Salamander in each uterus in the 

 method normal for S. atra — that is, if the original experimental 

 conditions are continued. Even if these conditions are not con- 

 tinued, they show the influence of their origin, though to a less 

 extent. For they either produce relatively advanced larvae in 

 the water, which possess long uterine gills and metamorphose 

 after a few days, or they produce larvae on the land which have 

 rudimentary gills, and are incapable of living in deep water. 

 These land larvae in a few days metamorphose to adult Sala- 

 manders, which from their small size and uniform black pigment 

 might readily be taken for the young of S. atra. It thus appears 

 that in every case an inheritance of the acquired developmental 

 characters has taken place. 



In a more recent paper Kammerer has published the results 

 of a similar series of experiments on Alytes obstetricans, the 

 Midwife Toad. The habits of this species in the wild state are quite 

 unusual. It propagates itself on land, and lays from eighteen 

 to eighty-six heavily-yolked eggs in a long chain ; this chain is 

 drawn out from the cloaca of the female by the male during the 

 act of copulation, and at the same time he wraps them round his 

 thighs. The gelatinous envelope of the eggs is very sticky, and 

 attaches them to his legs, and by subsequent shrinking the band 

 is drawn tight. While the male is in charge of the eggs he for- 

 sakes his usual habits, and diligently seeks for water in which 



