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and on other parts. The organs of 

 reproduction in mosses consist of 

 sporules, contained within an urn 

 or theca, placed at the top of a thin 

 stalk. In lichens, the organs of 

 reproduction are sporules. 



SPRINGS OF WA'TER. All permeable 

 strata receive rain-water at their 

 surface, whence it descends until it 

 is arrested hy an impermeable 

 subjacent bed of clay, causing it to 

 accumulate throughout the lower 

 region of each porous stratum, and 

 to form extensive reservoirs, the 

 overflowings of which on the sides 

 of valleys constitute the ordinary 

 supply of springs and rivers. The 

 water, however, which descended 

 from the atmosphere in the form of 

 rain, having passed through the 

 various strata, does not re-issue in 

 the same condition. Rain-water 

 contains carbonic acid ; in passing 

 through the strata it absorbs oxide 

 of iron, lime, &c., and on issuing in 

 the form of springs it loses its 

 excess of carbonic acid, and again 

 deposits carbonate of iron, &c. 

 " Springs are seldom or ever quite 

 pure, owing to the solvent property 

 of water, which percolating through 

 the earth, always becomes more or 

 less charged with foreign matter. 

 Carbonate, sulphate, and muriate 

 of lime, muriate of soda and iron, 

 are frequently present in spring 

 waters. Some are more highly 

 charged with these and other sub- 

 stances, such as carbonate of mag- 

 nesia and even silica, than others, 

 and have hence obtained the name 

 of mineral springs. Many thermal 

 springs contain silica, though this 

 substance is of exceedingly difficult 

 solution. Springs usually possess 

 one particular average temperature, 

 generally identical with that of 

 the ground through which the 

 particular spring passes." 



SQUA'LOID. (from squalus, a shark, 

 Lat. and e?o<?, resemblance, Gr.) 

 The squaloid, or third division of 



fossils of the family of sharks, 

 appears for the first time in the 

 chalk formations, and extends 

 through all the tertiary deposits to 

 the present period. 



SQTJA'LUS. The name given by Lin- 

 na3us to the true shark. 



SQUA'MOSE. ') (sguamosus, Lat.) Sca- 



SQTJA'MOTJS. j ly ; covered with scales. 



SQA'RROUS. (from squarra, roughness 

 of skin, Lat.) 



1. In conchology, consisting of 

 scales spreading every way, or 

 standing upright, and not parallel 

 with the plane. 



2. In botany, applied to parts with 

 scales widely divaricating. 



STAGONOLE'PIS. A genus of ichthyo- 

 lites of the old red sandstone. 



STA'LACTITE. (oraXa/cT^, from ora- 

 Xa^w, Gr. to drop or distil ; statac- 

 tite, Pr.) A concretion of carbo- 

 nate of lime pendent from the roof 

 of a cavern, and produced by the 

 percolation and dripping of water, 

 holding in solution, or super-satu- 

 rated with, carbonate of lime. The 

 mode of formation of a stalactite 

 resembles that of an icicle j the 

 water, as it slowly drips from the 

 roof, continually deposits upon the 

 pendent stalactite a small quantity 

 of its carbonate of lime, and thus 

 the stalactite increases in length 

 and bulk. 



STA'LAGMITE. (from o-TaX^/io?, Gr. 

 stalagmite, Pr.) A concretion of 

 carbonate of lime produced by the 

 dripping of water holding in solu- 

 tion carbonate of lime. The dif- 

 ference between a stalactite and a 

 stalagmite is this: the former is 

 attached to, suspended from, and 

 formed at, the roof of a cave or 

 grotto ; the latter is formed upon 

 the floor : the stalactite generally 

 resembles a large icicle ; the stalag- 

 mite is an unshapen mass upon the 

 floor. It sometimes happens that 

 from the stalactite lengthening 

 downwards, and the stalagmite 

 increasing upwards, the two be- 



