OK, PLAIN TEACHING. 



347 



two or three others of the same genus, is still 

 used in the manufacture of kelp, but not to 

 such an extent as formerly. When trodden 

 on, or otherwise suddenly compressed, the air 

 vessels explode with a slight report, and seem 

 to afford much gratification to juveniles. The 

 larger air vesseis of some of the other fuci, 

 when dried and thrown into a fire, explode 

 with a loud crack. 



These plants grow in the greatest abundance 

 on rosks that are covered by the waves at high 

 water, and left bare when the tide retires 

 Now on, under, and among these rocks, the 

 great zoological or botanical harvest is to be 

 gleaned, and therefore among these rocks the 

 collector must walk. It is necessary to warn 

 the enthusiastic naturalist, that the slimy and 

 slippery fuci make the rock-walking exceed- 

 ingly dangerous ; for the masses of weed are 

 so heavy and thick, that they veil many a 

 deep hollow, or slightly cover many a sharp 

 point ; in the former of which a limb may be 

 broken, and by the latter a serious wound' in- 

 flicted ; and there is special reason for avoiding 

 such a mishap. Proverbially, time and tide 

 wait for no man ; and should a disabling acci- 

 dent occur when no one was near to help, the 

 returning waters would bring death in their 

 train.* We have found a pair of thick shooting 

 boots, with heavy, sharp-headed nails, the best 

 for taking hold of the rocks, through the 

 masses of weeds. 



It may be as well to state that the tea weeds 

 are arranged by naturalists into three divisions : 

 chlorospermece, the green and simpler kinds ; 

 rhodospermece, the red and purplish ; and me- 

 lanosper mece, the olive, brown, and black. These 

 names are derived from Greek words, meaning 

 respectively green, red, and black ; and sperma, 

 seed. 



In examining them, notice should be taken 

 of their roots, whether discous or fibrous; of 

 their habitat, whether on pebbles, rocks, shells, 

 wood, &c. ; of their sporules, or fructification, 

 whether attached to the midrib, prevailing 

 throughout the frond, or in terminal, or other 

 receptacles ; the time of the year in which they 

 are found, either with or without fruit, should 

 also be noticed ; and also the state of the tide, 

 and the character of the shore; attention 

 should also be paid to the molluscs, to coral- 

 lines, polypi, and animalcules, that may be 

 found attached to them. It should also be 

 borne in mind, that in the botanical order algoe 

 are included the minute plants forming a scum- 

 like covering to the waters in ponds and rivers. 



These vegetable productions of the sea have 

 their uses in the economy of nature in other 

 respects than those we have already pointed 

 out. They soften the currents of the rolling 

 waters, and lessen the violence which would 

 otherwise assail the shores of the land; they 

 also serve as food for many of the larger 

 aquatic reptiles, as, for instance, the green 

 turtle ; and they afford a kind of forest shelter 

 to myriads of the smaller living creatures which 

 Inhabit the sea; and afford lodgment for the 

 eggs of fishes. 



Let us now turn to some of 

 the curious animal forms found 



♦ K*v J G. VVo-'d's Common Objects of the Pea 

 Shore. 



upon the shore ; and first to that 

 seemingly anomalous creature, 

 the hermit-crab, 11. These crabs 



. 11 



1159. 



are soft-tailed creatures, and, in 

 the absence of a shell to cover 

 their posterior extremities, they 

 occupy the empty shells of whelks, 

 or other molluscs, as they may 

 happen to find them. As they 

 grow they are occasionally obliged 

 to quit their old tenement, and 

 seek a larger one. Its manner of 

 doing this is thus described by 

 the Rev. J. G. Wood :— 



When a hermit desires to change his habi- 

 tation, he goes through a curious series of 

 performances, which, if he had hands, we should 

 be disposed to call manipulations. A shell lies 

 on the ground, and the hermit seizes it with 

 his claws and feet, twists it about with wonder- 

 ful dexterity, as if testing its weight ; and 

 having examined every portion of its exterior, 

 he proceeds to satisfy himself about the inte- 

 rior. For this purpose he pushes his fore legs 

 as far into the shell as they will reach, and 

 probes with their assistance every spot that 

 can be reached. If this examination satisfies 

 him, he whisks himself into the shell with such 

 rapidity, that he appears to have been acted 

 upon by a spring. 



Helpless as these poor hermits 

 look, and tossed about as they 

 sometimes are by the waves, 

 when from a scarcity of shells 

 they are obliged to occupy tene- 

 ments too big for them to manage, 



