368 LEON J. COLE. 



The question naturally arises, however, in the light of Jennings' 

 observations that there is commonly a preference for the use of 

 certain rays in righting, whether these same rays will be the first 

 to turn if all are detached and inverted, and whether they will 

 twist in the same direction as when helping to right the entire 

 starfish. Will subsequent locomotion also be in the direction 

 with respect to each of the arms that it would have been if the 

 arms were attached ? 



The detached arms have two principal methods of righting 

 themselves when inverted. The first is to curl up orally until 

 they topple over one way or the other, when the tu.be feet attach 

 and quickly right the arm. The other method is for the tip of 

 the arm to twist until the tube feet can attach. They then 

 start to crawl and the remainder of the arm is soon pulled over 

 much after the manner in which a flatworm rights itself (Pearl, 

 '03, p. 673). A sufficient series of experiments was not per- 

 formed to answer the questions propounded above, the results 

 so far as obtained being somewhat contradictory. More ex- 

 tended experiments, however, would probably lead to more 

 definite results. 



CONCLUSIONS. 



As stated, the experiments mentioned above were rather inci- 

 dental to other experiments on the starfish already reported 

 (Cole, '13) and preliminary to others which it was hoped to 

 continue. They are reported now not so much for the value of 

 the results obtained as in the hope that they may stimulate fur- 

 ther work along the same line. They do, however, seem to 

 demonstrate, in so far as they go, the failure of the establishment 

 of coordination or "unified impulses" in the starfish by direct 

 pull of one part upon another when the nervous connection 

 between these parts has been severed. 



LITERATURE CITED. 



Cole, L. J. 



'13 Direction of Locomotion of the Starfish (Asterias forbesi). Journ. Exper. 



Zool., Vol. 14, No. i, pp. 1-32. 

 Friedlander, B. 



'88 Ueber das Kriechen der Regenwiirmer. Biol. Centralblatt, Bd. 8, Nr. 12, 

 PP- 363-366. 



