138 MANUAL OF THE MOLLUSCA. 



of an experienced concliologist, Mr. W. J. Broderip : — " "When 

 the tide is at the lowest, the collector should wade among the 

 rocks and pools near the shore, and search under overhanging 

 ledges of rock as far as his arms can reach. An iron rake, 

 with long close-set teeth, will be a useful implement on such 

 occasions. He should turn over all loose stones and growing 

 sea-weeds, taking care to protect his hands with gloves, and his 

 feet with shoes and stockings, against the sharp spines of Echini, 

 the back-fins of sting-fishes, and the stings of Iledusce. In 

 detaching chitons and limpets, which are all to be sought for 

 on rocky coasts, the spatula or case-knife will prove a valuable 

 assistant. Those who have paid particular attention to j)re- 

 serving chitons have found it necessary to suffer them to die 

 iinder pressure between two boards. Ormers [Haliotides) may 

 be removed from the rocks to which they adhere by throwing a 

 little warm water over them, and then giving them a sharp 

 push with the foot sideways, when mere violence would be of 

 no avail without injuring the shell. EoUed madrepores and loose 

 fragments of rock should be turned over; cowries and other 

 shell-fish frequently harbour under them. Numbers of shell- 

 fish are generally to be found about coral-reefs." In coral region? 

 the services of natives should be obtained, as they may render 

 much assistance by diving or wading. 



Advantage may be taken of spring-tides, especially at the 

 equinoxes, to examine lower tracts of sea- shore than are ordi- 

 narily accessible. Many bivalves bury in sand and mud at 

 extreme low-water, and may be obtained alive by digging with 

 a spade or fork; others may be found boring in piles and rocks, 

 and require the hammer and chisel for their extraction.* 



Mr. Joshua Alder remarks that ' ' in collecting among rocks 

 the principal thing is to look close, particularly in crevices and 

 under stones. Minute species inhabiting sea-weed are best 

 obtained by gathering the weed and immersing it for some time 

 in a basin of sea-water, when the little mollusks will generally 

 creep out. If the shells only are wanted, the surer and more 

 ready way is to plunge the weed into freshwater, when the 

 animals immediately fall to the bottom." 



The floating moUusca of the open sea, especially in tropical 

 latitudes, are comj^aratively little known. Good drawings, and 

 descriptions made from the life, are most valuable. "Of the 

 animal of the Spirula, entire specimens are greatly wanted. If 



* Bivalves may be boiled, and their soft parts removed when the shells gape. Care 

 Bhouid be taken not to injure the ligament, or hinge, especiallj' in the genera (like the 

 Arjztinid) provided with an ossicle. 



