38 



corals and corallines, and those minute animals from which the 

 medusae are developed. And 12th. Sponges. 



Localities and Stations. — Where the retreat of the tide is 

 sufficient, the sea-shore always affords the best field for the col- 

 lector, and the specimens generally increase in number and interest 

 iu proportion as we approximate to low-water-mark. Neverthe- 

 less the whole area should be searched, as each species has its 

 peculiar range, and many forms can live only where they are ex- 

 posed to the air for a greater part of the time each day. The 

 ground may be either muddy, sandy, weedy, gravelly, stony or 

 rocky, and the animals inhabiting each kind of ground will be 

 found to be more or less peculiar to it, and rarely to occur on the 

 others. Sand and mud are, however, so similar in character that 

 their denizens are nearly the same, though some prefer the clearer 

 waters which flow over sand, to the turbid tide which deposits 

 mud. But few specimens will be found on the surface of such 

 ground, although the little pools lying upon it should be scooped 

 with the dip net for shrimps, etc., but it is only by the spade that 

 its true riches can be developed. By digging in spots indicated 

 by small holes, a great number of worms, boring crustaceans, and 

 bivalves may always be found. Weedy ground is so called from 

 the abundance of eel-grass and sea-weed which covers it. These 

 weeds should be examined carefully for small shells and crustaceans; 

 perhaps the best method of doing this being to wash quantities of 

 the weed in a bucket of water and examine the sediment. Gravelly 

 ground is not generally very rich in animal life, but will repay an 

 examination, as small crabs are fond of lurking among the pebbles. 

 Stony ground is by far the richest of all. Wherever there are 

 stones, particularly flat ones, about large enough to afford a mode- 

 rate degree of exercise to a common sized man in turning them 

 over, there the zoologist can never fail to fill his basket and bottles ; 

 for beneath these stones myriads of rare and beautiful species retire 

 for moisture and protection during the retreat of the tide. Rocky 

 ground should be searched chiefly in the pools and crevices. 



Littoral or sea-shore investigations should be carried on not only 

 in the bays, harbors, and creeks, but on the ocean beach, in each 

 locality, to get at a true idea of its fauna, as the respective animals 

 ■^ill be found different. 



Dredging. — A large proportion of the marine invertebrates never 

 approach the shore closely enough to be left exposed by the tide, 



