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ranked among fishes. Its form 

 was adapted for swimming. 



SAI/BOID. (from tmvpa, a lizard, and 

 ei8o?, form, Gr.) The name given 

 to a group of fishes found in great 

 abundance in the carboniferous and 

 secondary formations. The sauroid 

 fishes occupy a higher place in the 

 scale of organization, than the or- 

 dinary forms of bony fishes. In the 

 tertiary strata the sauroids almost 

 disappear, and are replaced by less 

 complex forms. The sauroid, or 

 lizard-like fishes, combine in their 

 structure, both in the bones and some 

 of the soft parts, characters which 

 are common to the class of reptiles. 



SATJ'SSTJRITE. A combination of crys- 

 tallized serpentine with jade or 

 felspar. The jade de Saussure of 

 Brongniart. In its external cha- 

 racters it differs but little from 

 nephrite, but in its composition it 

 by no means resembles it. It was 

 first noticed by Saussure near the 

 lake of Geneva, scattered about in 

 rounded pieces and loose blocks. 

 Its colours are green, greenish 

 grey, or white with a slight tinge 

 of green or blue. Its specific 

 gravity is about 3*35. Before the 

 blow-pipe it fuses. It consists of 

 silex 49-0, alumine 24'0, lime 10'5, 

 soda 5*5, magnesia 3'75, oxide of 

 iron, 6*5. By many mineralogists, 

 Saussurite is included under ne- 

 phrite. 



SAXICA'VA. A genus of bivalves, be- 

 longing to the family Lithophagi, 

 or stone-eaters. 



SAXICA'VOTTS. Animals which make 

 holes in the rocks, either by boring 

 them, by means of some auger-like 

 process they possess; or by dissolv- 

 ing the rock, by some acid which 

 they secrete. 



SAXIGENOTJS. Producing stone. This 

 term is more particularly applied 

 to those polypi which produce the 

 reefs and islands of coral, so abun- 

 dant in the Pacific Ocean and 

 Indian seas. 



SCA'BROTTS. (from scabrosus, Lat.) 



1. In entomology, applied to the 

 surface of an insect when covered 

 with small and slight elevations. 



2. Applied to shells, when rough, 

 rugged, harsh, or like a file. 



3. In botany, applied to stems that 

 are rough, from any little inequali- 

 ties or tubercles. 



SCA'GLTA. (Ital.) A kind of chalk, 

 of a red colour. In an interesting 

 paper, by Prof. Sedgwick and Sir 

 E. Murchison, published in the 

 Philosophical Magazine for June 

 1829, on the relations of the secon- 

 dary and tertiary strata on the 

 southern flanks of the Tyrolese 

 Alps, the tertiary strata are 

 described as forming a vast series 

 of beds resting on scaglia or chalk. 

 The scaglia occurs in beds nearly 

 vertical; the upper ones contain 

 nodules and layers of flints ; their 

 colour is red, and their structure 

 fissile. The scaglia contains in some 

 parts ammonites and belemnites. 



SCALA'BIA. A genus of marine tur- 

 reted univalves, with acute longi- 

 tudinal raised ribs. The aperture 

 nearly circular ; the margins unin- 

 terrupted, bordered, and reflected. 



SCA'NDENT. (from scandens, climbing, 

 Lat.) A term applied to plants 

 which climb upon some support, 

 attaching themselves by fibres or 

 tendrils. 



SCANSO'RES. The second order of the 

 class aves, or birds; the woodpecker, 

 cuckoo, and parrot are examples. 



SCAPE. (from scapus, Lat.) In 

 botany, an herbaceous stalk, spring- 

 ing from the root, and bearing the 

 flower and fruit, but not the leaves. 

 The hyacinth is an example. 



SCA'PHITE. (from scapha, a boat.) 

 So named from its supposed resem- 

 blance to a boat. The scaphite 

 resembles an ammonite partly un- 

 rolled, Scaphites are found in the 

 chalk, and in the greensand ; they 

 are believed to be altogether 

 extinct. 



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