NO. 19.] ECHINODERMS OF CONNECTICUT. 29 



The general mode of life of the starfish, including habitat, 

 locomotion, changes in shape of body, and migration, are briefly 

 discussed in the following chapters, and the nature of this Report 

 does not justify further details. The subject of habit formation, 

 however, as described by Jennings* may be briefly outlined here. 



" The behavior of the starfish is in general characterized 

 by what might be called versatility; the animal can do in many 

 different ways anything that it can do at all." In its locomotion, 

 for example, it may move with equal facility in any direction 

 along the plane of its body without any regard to right or left, 

 or forwards or backwards. Under the same conditions its be- 

 havior is subject to the greatest variations, and it may be said 

 never to do the same thing twice in exactly the same way. 



When subjected to experiment it was found to solve the prob- 

 lem set for it, such as escaping from cramped quarters, removing 

 rubber bands from its rays, etc., in a great number of different 

 ways on successive occasions. But whenever left to itself it 

 showed no improvement in solving these problems. It never 

 learned to select the most effective method ; that is, it failed to 

 form the habit of employing this method when confronted again 

 with the same problem. 



But attempts to train the starfish were not altogether un- 

 successful; for example, when placed on its aboral surface, 

 the animal may right itself by employing any two adjacent arms, 

 different pairs being used on successive occasions. Yet by pre- 

 venting the use of certain arms the animal may be success- 

 fully trained to use certain other arms on all occasions. But the 

 effects of this training are soon lost, so that on the following 

 day the starfish shows no effect of its training. By giving the 

 animal ten lessons a day for eighteen days, however, the starfish 

 may show the effect for at least a week. By long continued 

 training it is probable that still more lasting habits might be 

 induced. 



FOOD 



One of the species of asteroids occurring in Connecticut 

 waters, the common starfish (Asterias forbesi), causes a vast 

 pecuniary loss each year because of the enormous numbers of 



•Johns Hopkins Univ. Circulars, No. 3, 1907; also Univ. Calif. Publications in 

 Zoology, vol. 4, 1907- 



