PRESIDENTIAL ADDRESS. 37 



or swimming animals. Though useful in the area for which 

 it was suggested, this classification is not of general appli- 

 cation. Progression methods are not as sharply defined 

 in the dense water as in the thin air, thus the glide of a 

 marine animal may change imperceptibly from crawling to 

 swimming. Neither areas nor animals can be definitely 

 arranged thus, for the upper rock zone is deficient in bur- 

 rowing and swimming species. A Oephalopod might 

 appropriately enlist in every company. Finally the sand- 

 surf organisms do not strictly belong to any particular 

 class, yet all might qualify for each. 



No marine community leads so strenuous a life as does 

 the sand beach fauna. In the sand-democracy organisms 

 are independent, there are no dominant types like Cynthia, 

 Ostrea or Oaleolaria to afford protection to the weaklings. 

 Since there are no plants, the animals are necessarily 

 carnivorous; since the even surface offers no shelter, the 

 only means of refuge is to plunge under the sand. Exist- 

 ence in the surf-line can be maintained only by great 

 strength, constant activity and watchfulness. An instant's 

 weakness, a moment's relaxation may bring destruction 

 either from being seized by a prowling fish, or from being 

 thrown high and dry upon the shore by the next wave. To 

 resist a blow the shells of the sand-dwellers are solid, to 

 dive quickly into the sand, they are smooth and tapering. 



Characteristic of the sand beach is the handsome white 

 and purple Donax deltoides (fig. 5), which in New South 

 Wales is called the " pipi," and in South Queensland is 

 known by the local aboriginal name of " ugari." Pipi is a 

 Polynesian word which has been adopted from the Maori. 

 In New Zealand pipi means Mesodesma australe, and in 

 Samoa it signifies Asaphis defiorata. 1 Stacks of shells in 



1 Bulow, Internat. Archiv. Ethnograpjti., xiii, 1900, p. 184. 



