REACTION IN ASTERINA GIBBOSA. 425 



Kipechnen E : ca. 25 mm. Rather shoi-t rays and big body. 14/6/19. 



38 sees. Turned on adjacent pair. 



36 „ Three at first, one gave up early, turned on adjacent pair. 

 32 ,, Three, then four, turned on adjacent pair. 



28 „ Five attached, „ „ 



30 „ Three attaclied, ,, „ 



32 ,, Turned on adjacent pa-r. 



33 „ Three at first, then turned on adjacent pair. 

 25 „ „ 



37 ,, Princiijallj' on one of an adjacent pair. 



23 „ Three for a ver^' short time, turned on adjacent pair. 



Average time 31-4 sees. 



Specimen F: ca. 32 mm. 16/6/19. 



115 sees. Three attached and transitory deadlock occurred, then a fourth 

 attached and the opposite outermost let go. Turned on three 

 adjacent. 

 45 ,, Three, then five, turned on two adjacent. 



115 ,, Turned on two, but second choice. Interfered with by surface-film 



which caused exploratorj' movements of tube-feet. 



Transferred to deeper part of pool : — 



45 sees. Turned on two adjacent. 



35 „ Three attached, turned on two adjacent. 



43 „ Four attached, then turned on two adjacent. 



60 ., Four, then three, then turned on two adjacent. 

 58 ■„ 



38 ,, Two, the)i three, then four, turned on adjacent pair. 

 45 „ 



This specimen showed a distinct tendency to attach all arms. 



Specimen G: ca. 14 mm. 16/6/19. 



45 sees. Two, then three, turned on adjacent pair. 



30 ., Turned on adjacent pair. 



25 



33 



28 

 22 



Three, then turned on adjacent pair. 



Turned on adjacent pair. 



One attached, then turned on adjacent pair. 



Average time 28'3 sees. A small and very active specimen. 



Specimen H: ca. 22 mm. 16/6/19. 



55 sees. Three, then four, then turned on adjacent pair. 



30 ., Four, then turned on adjacent pair. 



205 „ Deadlock I. (see below, p. 429). 



38 ,, Two, three, turned on adjacent pair. 



33 ,, Two, three, four, then turned on adjacent pair. 



615 ., Deadlock II. (see below, p. 429). 



195 „ Deadlock III. (see below, p. 429). 



42 ,, Two, four, three, then turned on adjacent pair. 



33 „ Three for very short time, turned on adjacent pair. 



48 „ Two, three, turned on adjacent pair. 



Specimen Z : ca. 31 mm. 18/6/19. 



72 scL's. Two, three, four, three, finally turned on adjacent pair. 



60 ., Four, three, turned on adjacent pair. 



52 ,, Three for very short time, turned on adjacent pair. 



