4O Studies in Animal Behavior 



rental affection, even of the most rudimentary sort. 



A more advanced stage in the evolution of pa- 

 rental care comes with the appearance of instincts 

 for more or less continuous care of the eggs after 

 they are laid. If the cocoon of the running spider 

 is taken away from her, which is done only after 

 a certain resistance, she will eagerly seize it again if 

 she happens to encounter it. The egg mass is treated 

 as an object of interest, although the young which 

 issue from it are regarded with indifference. In- 

 stincts for remaining with the eggs for a longer or 

 shorter time after they are deposited are not infre- 

 quent among fishes, and especially among those spe- 

 cies which expend some labor in the construction of 

 a nest. Generally this task is performed by the male, 

 as in the sticklebacks and the common Amia or dog- 

 fish of our ponds and streams. The males of these 

 fishes remain in or near the nest after the eggs are 

 laid, and they keep on the alert to drive away any 

 intruder that ventures too near. 



The Amphibia, which as a group are remarkable 

 for queer breeding habits, show in many cases primi- 

 tive instincts for guarding or at least remaining close 

 by the eggs during the early stages of their develop- 

 ment, although most species, as in our ordinary frogs 

 and toads, simply abandon their eggs as soon as they 

 are deposited. The newt Desmognathus lays its 

 eggs in a small hollow and remains near them for 

 some time. The snake-like caecilians coil about their 

 egg masses, and certain species of frogs carry eggs 



