i 3 4 HABITUDES AND ATTITUDES 



toad is afforded by a Ceylon frog Rhacophorus 

 (Polypedates] reticulatus as described by Giinther. 1 

 Here the ova, about twenty in number, were 

 found attached to the abdomen of the female, 

 and when detached they adhered firmly together 

 so as to form a flat disc. In the European Mid- 

 wife toad, Alytes obstetricans, the mode of nursing 

 is analogous to that of Rhacophorus reticulatus, 

 except that in Alytes it is the male that takes 

 care of the spawn. 



In illustration of the widespread nature of the 

 phenomenon of convergence may be mentioned 

 a case of brood-nursing on the part of some 

 insects. The family of amphibious water-bugs, 

 Belostomatidae, is noted for the possession of 

 the habit of carrying the eggs in the form of 

 a disc cemented upon the back of the male, to 

 which they are attached by the female. 2 A 

 species of this family where the habit can be 

 observed with comparative ease is Sphcerodema 

 rusticum Fabr., which occurs in the tanks of 

 Ceylon amongst the weeds at the margin. The 

 eggs remain on the back until the young hatch 

 out into the water. 



Amongst fresh - water fishes many cases of 

 convergence are found in respect of the manner 

 in which they prepare their nests and deposit 

 their eggs. One pair of examples will suffice, 



1 Ann. Nat. Hist., May, 1876, p. 379. 



2 Cf. W. L. Distant, "Rhynchota," vol. iii., Fauna Brit. 

 1906, p. 34. 



