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S T A 



Sponges assume a great variety of 

 shapes, each according to its species, and 

 resemble shrubs, globes, tubes, fans, 

 vases, &c., &c. For a description of 

 living sponges, the reader is referred to 

 the article Porifera. 



SPO'NGEOUS. (spongieux, Fr.) Of the 

 nature of sponge ; full of small pores. 



SPO'NGIFORM Q.UARTZ. The name given 

 to a white or grey, porous, variety of 

 quartz, so light as to swim on water, and 

 also called Floatstone. 



SPO'NGIOLE. In botany, an organ situated 

 at the extremity of the root, and thus 

 named from its peculiar texture. It is 

 by the spongioles, thus situated, that 

 plants are enabled to absorb. They are 

 constructed of common cellular spongy 

 tissue, and they imbibe the fluids which 

 are in contact with them, partly by capil- 

 lary action, and partly, also, by a hygro- 

 scopic power. 



SPO'RULE. (from ffiropa, a seed, Gr.) The 

 organ of reproduction in cryptogamic 

 plants. Ferns are increased by minute 

 bodies, called sporules ; these are pro- 

 duced either on the backs, or in the axillse 

 of the fronds, and on other parts. The or- 

 gans 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," says Prof. Buckland, " receive 

 rain-water at their surface, whence it de- 

 scends until it is arrested by an imperme- 

 able subjacent bed of clay, causing it to 

 accumulate throughout the lower region 

 of each porous stratum, and to form ex- 

 tensive 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 car- 

 bonate of iron, &c. Springs usually pos- 

 sess one particular average temperature, 

 generally identical with that of the ground 

 through which the particular spring 

 passes. That the generality of springs 

 owe their supply to the atmosphere is 

 evident from this, that they become lan- 

 guid, or entirely cease to flow, after long 

 droughts, and are again replenished by 

 copious showers of rain. For the con- 

 stancy and uniformity of their volume 

 they are most probably indebted to the 

 large extent of those subterranean reser- 

 voirs with which they communicate. 



SPUNGE. See Sponge. 



SHUA'LOID. (from squalus, a shark, Lat. 

 and tWoQ, resemblance, Gr.) The squa- 

 loid, or third division of fossils of the 

 family of sharks, appears for the first 

 time in the chalk formations, and ex- 

 tends through all the tertiary deposits to 

 the present period. Species of the squa- 

 loid division only, abound in all the strata 

 of the tertiary period. 



SQUA'LUS. The name given by Linnaeus to 

 the true shark. 



SCIUA'MOSE. } (squamosus, Lat.) Scaly; 



SQUA'MOUS. $ covered with scales. 



SQ,UA'RROUS. (from squarra, roughness of 

 skin, Lat. str^dpa, Gr.) 



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. 



STALA'CTIC. ^ Resembling stalactite ; of 

 STALA'CTICAL. $ the character and ap- 

 pearance of stalactite. 



STALA'CTITE. ((rraXa/crig, from 0ra\aw, 

 Gr. to drop or distil ; stalactite, Fr.) A 

 concretion of carbonate of lime pendent 

 from the roof of a cavern, and produced by 

 the percolation and dripping of water, 

 holding in solution, or super-saturated 

 with, carbonate of lime. The mode of 

 formation of a stalactite resembles that 

 of an icicle ; 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 stalac- 

 tite increases in length and bulk. 

 STALACTI'TIC. ) Synonymous with sta- 

 STALACTI'TICAL. $ lactic and stalactical. 

 STALA'GMITE. (from 0ra\ay|u6f, Gr. sta- 

 lagmite, Fr.) A concretion of carbonate 

 of lime produced by the dripping of water 

 holding in solution carbonate of lime. 

 The difference 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 

 stalagmite is an unshapen mass upon the 

 floor. It sometimes happens that from 

 the stalactite lengthening downwards, and 

 the stalagmite increasing upwards, the two 

 become united, and thus form a column 

 extending from the roof to the floor. 

 STALAGMI'TIC. ) (from stalagmite. ) Re- 

 STALAGMI'TICAL. $ sembling stalagmite ; 



containing stalagmite. 



STA'MEN. (stamen, Lat.) A constituent 

 part of a flower, situated within the 

 corolla, consisting of two parts, the fila- 

 ment and the anther. The stamens are 

 the male organs of the plant. In the 

 plural the word is written either stamens 

 or stamina. 



