Reactions of Sponges 



3i 



TABLE 2 



Summary oj the Reactions of the Oscula, Ostia, and Choanocytes of Stylottlla to t'arious Stimuli 



Mechanical Stimuli 

 Seawater currents. 

 Quiet seawater. . . . 



Brushing 



Silt 



Exposure to air. . . . 

 Injury 



REACIION BY 



Osculum 



Opens and remains open . , 

 Closes and remains closed 

 No reaction.' 



Closes and remains closed , 

 Closes 



Ostium 



No reaction. 

 No reaction . 

 No reaction. . 

 No reaction.. 

 No reaction. . 

 Closes 



Chemical Stimuli 

 0.5 per cent ether i Closes and remains closed 



0.5 per cent chloroform| Closes and remains closed 



1/15,000 strychnine. 

 1/1,000 cocaine . . . . 

 1/10,000 cocaine . . . . 



1/50,000 cocaine 

 1/1,000 atropine. 



Closes and remains closed 

 Closes and remains closed 

 Remains open; closure in- 

 hibited 



Remains open 



Remains open; closure in- 

 hibited 



1/10,000 atropine. . . . 

 3/4 seawater 4- 1/4 

 freshwater 



1/2 seawater + 1/2 

 freshwater 



1/4 seawater -I- 3/4 

 freshwater 



Freshwater 



Deoxygenated water. . 



Thermal Stimuli 



9° to 10° C 



25° to 28° C 



35°C 



Remains open 



Closes slightly, then re- 

 opens 



Closes quickly and remains 

 closed 



Closes quickly and remains 

 closed 



GradLially closes 



Closes and remains closed 



Remains open or if closed, 

 soon opens 



Remains open or if closed, 

 soon opens 



Contracts but does not 

 close 



Contracts but does not 



close 



Remains open but inactive 

 Closes 



Remains open, or if closed 

 opens 



Choanocyte 



Probably reinains open; if 

 closed, opens slighty. . .! 



No reaction 

 No reaction 

 No reaction 

 No reaction 

 No reaction 

 No reaction 



Currents soon cease 



Currents soon cease 



Currents strong 

 No reaction 



No reaction 

 No reaction 



No reaction 

 No reaction 



No reaction 

 Currents soon cease 



40° C. 

 45° C. 



Light 



No reaction 



Normal 



Slight constriction . 



Slight constriction . 

 Flabby contraction. 



Currents cease 

 Opens and remains open.| Currents strong, then 

 cease 



No reaction ! Currents become slow 



Normal ' Normal 



Remains open or if closedi 



opens Normal 



? Currents cease 



No reaction No reaction. 



Currents cease 

 No reaction 



