448 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 63 



ditions? We might well question the reasons for doing any basic 

 research, and, although many complex reasons might be given, the 

 closest we can come to a simple and direct answer would be to say 

 that any enlargement of our knowledge of the world about us is 

 worthwhile. The following discussion should provide a rationale for 

 the undertaking of a study of these corals. 



There are perhaps 50 species of corals to be found in the waters 

 of the Southern Ocean from the shallowest to the deepest portions. 

 This variety is somewhat easier to comprehend than the 400 or more 

 species recorded from the shallow waters on the reefs of the Fiji 

 Islands, a number which does not include all of those corals which 

 might be found by divers or by dredging and trawling in the deeper 

 waters around those islands. But more significant than the number 

 of kinds involved is the number of specimens which can be collected 

 per unit of effort. Antarctic corals, like most cold-water bottom 

 dwelling invertebrates, are not evenly distributed on the sea floor, 

 but rather are scattered in clusters in what has been called a "con- 

 tagious distribution." Trawl samples from the sea bottom do not 

 usually indicate a large variety of species present; they more often 

 yield large numbers of one kind of coral, with token representation 

 of other types. For example, in one dredge haul from Pennell Bank 

 in the Ross Sea, Antarctica, 141 specimens of one species were taken 

 together with 33 specimens belonging to three other species. In 

 contrast, a trawl made in the Sulu Sea by the Danish ship Sihoga 

 collected 55 specimens representing a total of 22 species. Although 

 bottom trawls cannot be taken as a means of collecting quantitative 

 samples of bottom fauna, they are at present the most efficient means 

 of collecting large samples, and the examples given are probably 

 significant in terms of magnitude if not m comparability of absolute 

 numbers. 



The Antarctic corals are generally small (seldom over 1 inch in 

 diameter) horn corals of solitary habit. A few species of colonial 

 corals are found, but these are loosely branching forms which construct 

 very open colonies. The solitary forms normally live free on the 

 bottom so that their shape is gently curved. Others are attached to 

 rocks, pebbles, or shells and are straighter and more fan shaped. 

 These forms are characteristic of the deeper water corals of all oceans 

 and in themselves are not unique. Reef corals, or more properly 

 hermatypic corals, are found in depths of water to no more than 90 

 meters while the deepwater or ahermatypic corals are found from the 

 surface to depths of to 6,000 meters. The term hermatypic was 

 proposed by J. W. Wells to include those corals which build reefs 

 (hence the derivation of the word) and therefore the ahermatypic 

 corals are non-reefbuilding. This distinction is an important one, but 

 not necessarily the easiest to recognize. Reef -building corals are able 



