of some Ceyhnese Tree-Frogs. 379 



dined to suppose that a species of Ixalus will be found to be 

 the progenitor. 



So much is evident, that the mass enveloping the ova of 

 this frog offers a much greater protection against mechanical 

 agencies than the gelatinous substance of the common frog- 

 spawn ; but whether the cells below its surface contain air, to 

 keep the whole body floating on the water, or whether they 

 contain water, to supply the embryos with the necessary 

 moisture if the spawn remain noi-mally out of the water, is 

 uncertain at present. 



Quite recently an instance of a tree-frog carrying its spawn 

 about with it has come under my observation (see PI. XX. 

 fig. C). In a small collection of Ceylonese frogs submitted 

 to my examination by Mr. W. Ferguson, F.L.S., there was a 

 frog which I consider to be Polyjyedates reticulatus, and which 

 had the ova attached to the abdomen when that gentleman 

 obtained it. The ova are now detached, but still firmly adhere 

 to one another, forming a flat disk. They have left shallow 

 impressions in the skin of the abdomen of the adult frog, corre- 

 sponding to the arrangement of the ova in the disk, but not 

 deep enough to efiace the granulations of the skin. The ova are 

 only twenty in number, of large size, viz. of the size of a hemp- 

 seed. The adult frog is a female, with a body scarcely 2 inches 

 long, and with the internal signs that the ova have been but 

 recently excluded. Unfoi-tunately we do not know whether 

 the specimen was caught in or out of the water. 



None of the other Batrachians which are known to take 

 care of their progeny resemble Polypedates rettculatus in this 

 respect. Pijm, Nototrema, and Ojnstlwdelphys carry their ova 

 on the back ; and in Alytes it is the male which takes care of 

 the spawn. In our Ceylonese frog the mode of attachment is 

 perfectly identical with that which I described in the Siluroid 

 genus Aspredo (Fish. v. p. 268). 



I trust that these notes, fragmentary as they are, yet contain 

 matter of sufficient interest to induce naturalists resident in 

 Ceylon to continue and complete these observations. 



I take this opportunity of adding the descriptions of two 

 new species of Ixalus from Ceylon. 



Ixalus Fergusonii. 



Similar in habit to /. variabilis. Snout rather flat, short, 

 pointed in front, with short but distinct cantlius rostralis, and 

 with the loreal region subverticah Eye of moderate size ; 

 tym})anurn hidden. U[)pcr parts smooth ; abdomen coarsely 

 granulated. Metatarsus without fringe or fold, and with a 



