MATING BEHAVIOR OF THE WOOD FROG. 1 75 



the pond or clings to debris well beneath the surface and comes 

 to the surface only occasionally. Even when unobserved by a 

 male the female apparently does not remain at the surface for 

 more than a few seconds at a time. When the female comes up 

 she usually dodges under again at once to avoid the approach 

 of one or more males. Sometimes she swims for a short distance 

 on the surface and then goes under but more usually she dodges 

 under at once and either remains beneath the surface or after 

 swimming with a few long effective strokes comes up again some 

 little distance away. The males follow a disturbance of the 

 surface almost as readily as the moving object itself. If a female, 

 though submerged, swims near enough the surface to produce 

 some little ruffling of it, one or more males is very likely to follow 

 the disturbance and attempt to seize the female when she comes 

 up. Once in a while the female leaves the water and with long 

 leaps moves about over the bank near the level of the water. 

 She (as well as any male moving on the bank near the water's 

 edge) may be pursued by males even here, though a capture on 

 land was not observed. 



The beginning of the attempt of a male upon a female is of 

 course not in any way different from his approach toward another 

 male but when he actually touches or often only nears the female 

 his actions are usually very different for instead of the vigor and 

 aggressiveness of the assailant rapidly falling off, as in case of one 

 male approaching another, the aggressiveness is tremendously in- 

 creased. The male makes every effort to catch the female if she 

 is about to escape and often follows her under the water a little, 

 but more often rapidly follows any disturbance of the surface 

 and attempts to seize the female at once on her reappearance. If 

 a male once succeeds in clutching with the fore legs any portion 

 of the body of a female he cannot be dislodged, though the female 

 continues to struggle. The male quickly brings himself to the 

 pairing position, sitting upon the female's back. The fore legs 

 are tightly clamped about the female with the first toes extended 

 and deeply depressed against the ventral body wall of the female 

 just back of the pectoral girdle. Often two or more males pursue 

 a female at the same time and in case one male gets a hold on the 

 dorsal side of the female and anterior to a second male the latter 



