74 THE SHORE 



the massive calcareous forms, as they vary so greatly 

 with environment. 



Of groups of free-living animals on tropic shores, 

 the fishes, Crustacea, starfishes (except the Crinoids), 

 and Mollusca, do not vary greatly in genera and species 

 over each of the two great geographical ocean areas, 

 the Atlantic and the Indo-Pacific. They are also 

 fairly well known, having always presented great 

 attractions to the collector, from their number and 

 beauty, and from the ease with which they can be pre- 

 served by being simply dropped into 90 per cent, 

 spirit ; they dilute this down to about 60 per cent, 

 by the time the tank or bottle is full. Crustacea and 

 starfishes should always be wrapped in cloth if they 

 are to be placed with many other animals in a large 

 receptacle, and a preliminary soaking in dirty spirit 

 of about 40 per cent, prevents Crustacea from getting 

 brittle and soft sea-urchins from getting distorted. 

 The sea-slugs, or Holothurians, should be injected by 

 mouth and by anus with 90 per cent, spirit, using a 

 syringe. Numbers of these groups of animals may be 

 found in pools, in the branches of corals which require 

 to be broken up to liberate them, in weeds, and under 

 stones ; they may be caught with the hands or by the 

 net. Large forceps are advisable for spiny sea- 

 urchins, and digging in sand will yield a few bivalves 

 (Lamellibranchs) and Holothurians (trepangs). A 

 few pence or pieces of tobacco (sticks, twenty-six to 

 the pound, price tenpence to a shilling) judiciously 

 expended among the natives, will bring in many of the 

 larger forms more difficult to catch. Heaps of stone 

 and corals, baited with coconut scraped up and 

 mixed with the ink of the cuttle-fish (or with pounded- 

 up land-crabs), piled on sandy flats, covered with 

 2 or 3 feet of water at low tide, were responsible for 



