378 Dr. A. GUnther on the Mode of Propagation 



coveries will be made by naturalists who have the opportunity 

 of observing these animals in their native countries. The 

 statement of Bello y Espinosa *, that the young of some frog 

 in Porto Rico, called "co-qui" by the inhabitants, do not 

 pass through a metamorphosis, but are provided with four legs 

 and are air-breathers when hatched, is deserving of accurate 

 inquiry, as it seems that in this frog, which is, perhaps, a 

 species of Hylodes^ the embryo passes through that part of the 

 metamorphosis that is generally undergone by the tadpole in 

 water, in the ovum itself. The observation of A. W. Aitkenf, 

 that in tropical parts of Australia certain frogs form a hollow 

 ball of clay, containing about half a pint of clear cold water, 

 in which they sojourn during the drought, is probably also 

 indicative of a provision to secure the safety of the spawn and 

 young. In other tropical countries frogs have been observed 

 to deposit their spawn in small accumulations of water formed 

 in the hollows of trees or branches. Some years ago Mr. E. 

 W. H. Holdsworth, F.L.S., brought me from Ceylon, pre- 

 served in spirit, a rounded, flattened, spongy-looking soft 

 object, of the size of a crow's egg^ which he believed to be the 

 spawn of some tree-frog. He informs me that he " found this 

 specimen hanging from the side of a stone cistern in the 

 garden at the Governor's house at Kandy ; it was about 

 8 inches from the surface of the water, which was at its usual 

 height in the cistern." The lump is of an indistinct greenish 

 colour, elastic, and offering the same resistance to the touch as 

 the lung of a reptile, which it resembles in the reticulated, 

 vesicular appearance of its sm-face. On making an incision 

 we find it to consist of an interlaced tissue enclosing larger 

 and smaller vacuities which may have been filled with air or 

 water. A few lines below the surface the ova are found, some 

 lodged in meshes of the tissue, others accumulated towards 

 the centre of the lump. The ova appear now as broAvn glo- 

 bules of the size of a large pin's-head. A second lump of 

 spawn, of precisely the same shape and size as the first, was 

 more recently sent by Mr. Bligh to Mr. Holdsworth, who 

 kindly gave it to me. This specimen was accompanied by a 

 great number of minute greenish tadpoles and two fully adult 

 specimens of Polypedates maculatus. Although I have no 

 doubt that the tadpoles are of the same origin as the spawn 

 described, I do not believe that either is the product of that 

 species, the ova of which, when mature, are at least twice the 

 size of those deposited in the spawn-lump. I am rather in- 



* Zoolog. Gart. Fraukf. 1871, p. 351. 

 t Trans. New-Zeal. Inst. ii. 1870, p. 87. 



