A s 



[ 40] 



AST 



named by Goldfuss A. quinqueloba, 

 the other has not yet been deter- 

 mined. Eight species found in the 

 oolite of Germany have been thus 

 named by Goldfuss, Munstcr, and 

 Schlotheim, A. arenicula, A.juren- 

 sis, A. lancelota, A. lumbricalis, 

 A. prisca, A. scutata, A. stellifera, 

 A. tabulata. Of the Linnaean 

 genus Asteria, M. Lamarck has 

 formed a family to which he has 

 assigned the name Stellerida, com- 

 prehending four genera. 



ASTE'RIATED. Radiated. 



ASTE'RIALITE. (from atnyp, and \i'6o<?, 

 Gr.) Fossilized, petrified, or silici- 

 fied asterias, or star- fish. 



ASTE'RID^;. ( The fourth order of the 



ASTERID'EA. ( class Echinodermata, 

 comprising the star-fish, &c. 



A'STERITE. \ (astroite, Er. Espece de 



A'STRAITE. / madrepore ou de corps 



A'STRITE. i marin, aur lequel on 



A'STROITE. j voit represente la figure 

 d'une etoile.) Star stone. 



This name is also given to certain 

 varieties of the perfect corundum. 



A' STEROID, (from ao-T^/3 andetSo?, Gr.) 

 The name assigned by Herschel to 

 some newly discovered planets. 



ASTERO'IDAL. Resembling a star-fish. 



ASTEROLE'PIS. A genus of ichthyolites 

 of the old red sandstone, known 

 also as chelonichthys, which latter 

 name has now been supplanted by 

 the former. Many species have 

 been described by Agassiz. 



ASTEROPHY'LLITE. (from a<m}/> and 

 <fiv\\ov, Gr.) A plant discovered 

 in the coal formation, and thus 

 named from the stellated disposition 

 of the leaves around the branches. 



ASTO'MATA. The second class of the 

 sub-kingdom Protozoa, comprising 

 the four orders, Spongiadse, Eor- 

 aminifera, Thalissicolidse, and Gre- 

 garinidae. 



ASTRE'A. A genus of saxigenous 

 polyi. The appearance of groups 

 of astrece, and other corals, is de- 

 scribed as being most beautiful 

 when viewed with the animals 



alive and in activity; looking down 

 through the clear sea-water, the 

 surface of the rocks appears one 

 living mass, and the polypi present 

 the most vivid hues. 



It is stated, by those who have 

 opportunities of observing, that the 

 species of saxigenous polypi which 

 constantly form the most extensive 

 coral reefs and islands belong to 

 the genera Meandrina, Caryophyllia, 

 and Astrea, but especially to the 

 latter; and that these are not found 

 at depths exceeding a few fathoms. 

 M. M. Quoy and Gamard observe, 

 that neither with the anchor nor 

 the lead, have they ever brought 

 up fragments of astrea3, except 

 where the water was shallow, about 

 twenty-five or thirty feet in depth, 

 though they found that the branched 

 corals, which do not form solid 

 masses, lived at great depths. 



Fifteen species of the genus 

 Astrea have been determined by 

 Goldfuss as met with in the mem- 

 bers of the chalk group : twenty- 

 four species also are described as 

 found in the oolite : one belongs to 

 the muschelkalk, namely, Astrea 

 pediculata: one species, A. undulata 

 has been found in the carboniferous 

 limestone : three species have been 

 discovered in the grauwacke. 



Parkinson thus describes the 

 genue Astrea : "A stony polypifer, 

 fixed, conglomerated, incrusting 

 other bodies, or formed in a sub- 

 globose but rarely lobated mass. 

 The upper surface set with sessile, 

 lamellated, round or subangular 

 stars, which are circumscribed. 

 The stars in this genus are circum- 

 scribed. The substance is never 

 raised in extended expansions, or 

 developed in leaves, as in the 

 Explanarice, or ramified like the 

 Madrepores" The same author 

 describes 31 species. 

 ASTRI'FEROUS. j Bearing stars; having 

 ASTRI'GEROTJS. } stars; carrying stars. 

 A'STRITE. See Asterite. 



