S U D 



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S IT P 



ing to the sub-kingdom Diplo- 

 neura or Helminthoida. Cuvier 

 placed Suctoria in his placoid order, 

 but by the more recent classification 

 of Muller and Owen they have been 

 removed from that high order and 

 carried down to the lower point in 

 the scale, which their inferior 

 standing so obviously renders the 

 natural one. 



ST/DES. (sudes, Lat. a spear.) A 

 class of spines comprising several 

 genera, as Sudes villarum, Sudes 

 for tali tiorum, &c. 



SUFFOLK CEAG. A marine deposit of 

 the older pliocene period. It con- 

 sists of beds of sand and gravel, 

 abounding in shells and corals. 



SU'LCATED. (from sulcus, a furrow, 

 Lat.) Furrowed ; grooved. 



1. In botany, applied to stems 

 marked with broad deep lines; 

 also to leaves having broad, deep, 

 parallel lines. 



2. In conchology, applied to shells 

 that are deeply furrowed, or marked 

 with ridges or broad furrows. 



S'ULCUS. Plural sulci. A broad 

 furrow or groove. 



SULPHATE, (from sulphur.) A com- 

 bination of sulphuric acid with any 

 salitiable base. 



SULPHITE. A combination of sul- 

 phurous acid with any salifiable 

 base. 



SU'LPHUR. (sulphur, Lat. sou/re, Pr. 

 %6lfo, It.) One of the simple or 

 elementary substances, and a non- 

 conductor of electricity. It is of 

 different shades of yellow, and 

 occurs either in masses or crystal- 

 lized. Specific gravity from l - 9 

 to 2'1. By friction it acquires 

 negative electricity. It is very 

 brittle and friable. Its equivalent 

 number is 16'1 ; its symbol, S. 



SU'LPHURET. A combination of sul- 

 phur with a metallic base ; as sul- 

 phuret of iron. 



SU'LPHUBET OF IRON. Iron pyrites. 

 This is very commonly found in 

 irregular and subglobular nodules 



and masses, in the chalk formation. 



SU'MMIT. (summitas, Lat. sommet, Pr.) 

 In conchology, the most elevated 

 point of the shell in which the 

 hinge is placed. 



SUPERFI'CIES. (superficies, Lat. super- 

 fide, Pr. c'est lonyeur ei largeur sans 

 profondeur.) The surface only of a 

 body; the exterior part. 



STJP'ERIOR ORDER. By some geolo- 

 gists it has been proposed to place 

 all the formations above the chalk 

 in an order to be named the " Su- 

 perior Order." The superior order 

 may be deemed synonymous with 

 the tertiary, or newest floetz rocks. 

 In the arrangement thus proposed 

 the division of all the formations 

 will be as follows. 

 1. Superior order ; the same as the 

 tertiary. 2. Supermedial order, 

 comprising the chalk and all other 

 formations downwards to the mag- 

 nesian limestone inclusive. 3. 

 Medial order, comprising the coal 

 measures, the carboniferous lime- 

 stone, and the old red sandstone. 

 4. Submedial order, synonymous 

 with the transition, comprising the 

 roofing slate, &c. 5. Inferior or- 

 der, consisting of mica, slate, gneiss, 

 granite, &c., &c. 



SUPERME'DIAL ORDER. This class in- 

 cludes, generally, all the secondary 

 formations more recent than the 

 great coal deposit, and between it 

 and the tertiary, supra-cretaceous, 

 or newest floetz class. This series 

 of strata comprises distinct groupes 

 well marked from each other, and 

 therefore entitled to the name of 

 separate formations. The super- 

 medial order admits of four prin- 

 cipal divisions. 1 . The chalk for- 

 mation. 2. The series of ferrugi- 

 ginous sands, including, and divided 

 by, theWealden. 3. The series of 

 oolites, including and terminating 

 with the lias. 4. Prom the lias 

 downwards to the coal, comprising 

 the new red sandstone and the 

 magnesian limestone. 



