1889-90.] Dr J. Murray & Mr R. Irvine on Coral Reefs. 109 
Table XYII. Showing the Effect of Simple Immersion in Sea 
Water on Certain Corals. 
The following series of experiments as to the solubility of Coral 
simply suspended in mass in sea water and allowed to remain under, 
as nearly as possible, the same conditions, for certain periods of 
time, was made by Mr J. Galbraith Ross, B.Sc. • 
The corals were dried at 100°-110° C., until the weight remained 
constant. 
The temperature of the water ranged from a little over freezing- 
point to 40° F. 
No. 
Species. 
Locality. 
Weight 
in 
grammes. 
Surface in 
square inches. 
Time of 
Immersion 
in days. 
Loss. 
1 . 
Oculina varicosa, 
St Thomas, W. I. 
16-3164 
,8 
20 
0-0748 
2. 
Madrepora scabrosa, 
Levuka, Fiji. 
21-8540 
16 
30 
0*1497 
3. 
Montipora foliosa, 
Amboyna. 
15-3334 
15 
46 
0*1223 
4. 
Goniastrcea multilobata, 
9 9 
Bermuda. 
26*4069 
12 
60 
0-0895 
5. 
Millepora ramosa, 
14*2373 
5 
60 
0-1513 
6. 
Millepora murrayi , 
Samboangan. 
13*0605 
8 
60 
0-0725 
7. 
Fungia discus, 
44-3132 
acciden 
tally de 
stroyed. 
8. 
Mceandrina strigosa , 
Bermuda. 
22-9932 
10 
45 
0-1447 
9. 
Madrepora aspera, 
Maetan, Zebu. 
25*3694 
10 
45 
0-0734 
10. 
Madrepora palmata, 
St Thomas, W. I. 
31-7357 
10 
45 
0*1707 
Reducing these results to unit surface and time, the relation 
between them will be better observed : — 
No. 1. 
9 9 
99 
9 9 
9 9 
2 . 
3. 
4. 
5. 
6 . 
9. 
10 . 
Loss by solution from 1 square inch per annum, 0*1706. 
„ „ „ 0*1138. 
„ „ ,, 0-0647. 
,, „ ,, 0-0453. 
,, ,, „ 0-1860. 
„ „ „ 0*0552. 
„ „ „ 0*1173. 
„ „ „ 0*0584. 
„ „ „ 0*1384. 
The above series proves that under the same conditions different 
species of coral are acted upon in different degrees by the solvent 
action of sea water. Further, it would appear that the more 
areolar or amorphous the coral is the greater the action as compared 
with the harder crystalline varieties. 
