Abstracted by Cleorge Howard Parker, author 

 Harvard University. 



The crawling of young loggerhead turtles toward the sea. 



Newly hatched loggerhead turtles find their way from their 

 nests to the sea in consequence of at least three factors: first, 

 positive geotropism, as shown in their tendencies to move down 

 slopes; second, their response to their retinal images, in that they 

 move toward regions in which the horizon is open and clear and 

 away from those in which it is interrupted by complicated masses, 

 and, third, their probable response to color, in that they move 

 toward blue areas rather than toward those of other colors 

 (Hooker). These animals are not appropriately described as 

 phototropic, for they do not move either toward a source of light 

 or away from it, but they are to be regarded as exhibiting a more 

 complex condition in that they respond to the details of their 

 retinal images rather than to these images as wholes. 



