Ixxviii Journal of Proceedmr/s. 



aquatic free larval stage being conseriuently altogether suppressed.* It 

 was well known that in certain species of Batrachia, as for instance the 

 Surinam Toad {Pipa Americana), the eggs are carried about by the female 

 until hatched into young toads, and the tadpole stage is passed within 

 the egg. And an American species of Tree-frog (Hylodes) lays its eggs in 

 the axils of leaves, where only a few drops of water could at any time 

 collect. 



The President said that he had listened to Mr. Wilson's observations 

 with very great interest. The phenomenon described he had long believed 

 to occur, but Mr. Wilson's was the first direct evidence on the point he 

 had met with. He entered into a full explanation of the bearing of the 

 instance observed upon the known facts with respect to the development 

 of some species of Urodela, in which the larval form is a perfect animal 

 (Axolotl) and one capable of reproduction, but which, under certain con- 

 ditions, becomes transformed into a creature formerly placed in quite 

 another genus {AmhJij stoma). It was very interesting to find in our native 

 species of Batracliia a tendency to retain permanently the larval form, 

 and he hoped Mr. Wilson would institute some experiments to discover, if 

 possible, the nature of the conditions leading to this abnormal retardation 

 of development. From Mr. Wilson's account he gathered that the tad- 

 poles could not land, and he would suggest that possibly free access to 

 land so as to be enabled to breathe air was necessary for the development 

 of the lungs, and consequently, by correlation of growth, for the appear- 

 ance of the perfect animal. 



Mr. Wilson promised to make some experiments as suggested. His 

 own impression was that plentiful and suitable food was necessary for due 

 development. The water in the bell-glass had evaporated to about half ; 

 it was clear and healthy, of a brown colour like a dark tojDaz ; the weeds 

 were bright green and in vigorous growth. But he fancied that the want 

 of plentiful and varied food had so far discontented the tadpoles that 

 they had neglected their proper functions and failed in their duty to 

 Nature ! As an instance of the adaptability of Batrachians to varied 

 conditions, he might mention that in years gone by he had seen, in a dry 

 stone quarry, pale yellow slender newts shrivelled and dried up to an inch 

 and-a-half in length, bones and all, and yet alive ; the same newts that 

 in a wet season, when the stone quarry stood three feet in water, were of 

 a dark fine colour, and wriggled their graceful way through the rocky 

 pools, active and well, measuring seven or eight inches in length. f 



* Since the above meeting Mr. Meldola lias reminded me that in the Eui'opean Land- 

 Salanianders (which are ovo-viviparoiis) the larv?e, when born, have sometimes lost their 

 external branchiie, and that in Salamandra atra the entire branchiate stage is passed 

 within the body of the mother. As, however, these Urodela are normally ovo-viviparous, 

 while the Anoura are oviparous, the fact does not much aid my suggestion, and I am 

 bound to say that I am not able to point to any positive confirmatory observations. I 

 shall be very glad of information. — W.C. 



t A valuable discussion of the whole subject will be found in Mr. Meldola's translation 

 of Dr. Weismann's ' Studies in the Theory of Descent,' London, Sampson Low, 

 Marston and Co., 1882. Vol. ii. pp. 555— 633.— Ed. 



