HIGH SCHOOL ZOOLOGY. 



97 



one of the most completely aquatic species. R. clamitans, the 

 green or spring frog, rarely leaves the water for any distance, 

 while the wood frog R. temporaria var. sylvatica is found 

 among the fallen leaves of forests, with which its colour is as- 

 similated, while the two remaining species, R. ])alustris, and ha- 

 lecina are both found in marehy places and are more varie- 

 gated in colouration, for there are four or two rows of black 

 spots on the greenish ground of the back. 



An interesting case of adaptation to an arboreal life is 

 offered by a species of Ranidse from the Malay Archipelago — 

 Rliacopliorus Reinhardtii — (Fig. 71) — in which the webs of 

 the toes are used as a parachute in leaping from tree to tree. 



Fig. 71. — Rhacophorus Reinhardtii. (After Brehm;. 



23. The remaining orders of Batrachia are only represented by fossils 

 from the coal measures and the overlying Permian and Triassic strata. 

 The teeth are generally complex in structure whence the name 

 Labyrinthodontia. In form they resembled the Salamanders, but some 

 attained a gigantic size, and others, such as those found by Sir W, Daw- 



