The same is true for the next distinctly more superior group. More 

 tests, for instance, might show some significant difference between 

 Florida Yellow, Inshore, Mediterranean Deepwater, and Rock Island 

 sponges, but with the present data from a relatively limited number 

 of samples, the only conclusions are that in water-holding power, 

 these sponges overlap in individuals even though they are all supe- 

 rior to the Grass sponges. Mediterranean Bengasi sponges, with the 

 highest values, within 95 percent statistical probability, definitely 

 hold more water per unit volume than do the Inshore, Deepwater, and 

 Rock Island sponges, but the Bengasi sponges cannot be said to be 

 more absorbent than are the Florida Yellow sponges. This test, in it- 

 self, is not too important. A brick made with the proper pore size, 

 for instance, theoretically can hold more water per unit volume than 

 can any sponge. 



Table 13 • — Water-holding power 



Type of sponge 



Number of 

 sponges tested 



Average 



Standard 

 deviation^/ 



Fiducial 

 limits2/ 





25 



2k 

 26 

 28 

 28 

 25 

 2U 



Percent 



Percent 



5.U 

 8.5 

 7.U 

 7.0 

 9.9 

 2.6 

 k.9 



Percent 



Mediterranean Bengasi 

 Florida Yellow 

 Inshore Sheepswool 

 Mediterranean Deepwater 

 Rock Island Sheepswool 

 Hudson Grass 

 Anclote Grass 



53.6 

 U9.0 

 U6.2 



U5.9 

 U3.8 

 37.8 

 36.5 



51.U-55.8 

 U5.U-52.6 

 U3.2-U9.2 

 U3.2-U8.6 



39.9-U7.6 

 36.7-38.8 

 3U.5-38.6 



i/This column shows the variability in water-holding power among 

 sponges of a given type. The larger the number in this column, the 

 greater the variability in water-holding power, 



lJ This column indicates the limits within which the averages of 

 the samples will fall 95 times out of 100. With Mediterranean Ben- 

 gasi sponges, for example, the average water-holding power will be 

 expected to fall between 51.U and 55.8 percent in 95 out of 100 

 samples of 25 sponges each. 



U2 



