RUELLIA. 



[ 672 ] 



SALICORNARIA. 



BIBL. Decaisne, Ann. Sc. Nat. 2. xii. 

 251 ; Ann. N. H. vi. 257. 



RUEL'LIA. A genus of Acanthaceous 

 plants. The testa of the seed of Ruellia 

 formosa exhibits a peculiar kind of HAIR 

 '(PI. 28. tig. 21). 



RUST OF PLANTS. See BLIGHT. 



RUTILA'RIA, Gr. A genus of Diato- 

 macese. Frustules compressed, forming a 

 short filament ; valves elliptical, elevated at 

 the angles, with a central no'dule, termina- 

 ting in two short processes ; margin spinous. 

 3 species ; in the Barbadoes deposit. (Gre- 

 ville, Tr. Mic. Soc. 1866, 124.) 



RYE. The grain of Secak cereale. See 

 STARCH. 



RYLAND'SIA, Gr. & Ralfs. A genus 

 of Diatomaceae. Frustules simple, disk- 

 shaped, areolar ; valves with two opposite 

 smooth rays, dilated at their base, not 

 reaching the centre. It. biradiata, Barba- 

 does deposit. (Greville, Qu. Mic. Jn. 1861, 

 67.) 



RYTIPHLCE'A, Ag. A genus of Rho- 

 domelacese (Florideous Algae), containing 

 four British species, mostly common, having 

 pinnately branched, filiform or compressed 

 fronds, transversely striate and reticulated ; 

 the articulate axis is composed of a circle of 

 large elongated tubular cells surrounding a 

 central cell, the whole enclosed by a kind 

 of rind of several layers of small coloured 

 cells. Colour mostly dull red or brown. 

 Fronds from 2" to 4" or 6" high. Cera- 

 midia scattered on the ramules of some 

 plants ; antheridia tufted in the same situ- 

 ations on others ; and tetrahedral tetra- 

 spores occur imbedded in a double row in 

 stichidia, borne on distinct plants. R. pinas- 

 troides (PI. 4. fig. 11). 



BIBL. Harvey, Mar. Alg. 80 ; Grev. Alg. 

 Br. ; Derbes and Solier, Ann. Sc. Nat. 3. 

 xvi. 275 ; Thuret, ibid. 4. iii. 20. 



S. 



SACCAM'MINA, Sars. See LITUOLIDA. 



SACCOG'YNA. A genus of Junger- 

 rnanniese (Hepaticae) founded on Junger- 

 mannia viticulosa of Linnaeus ; it is re- 

 markable on account of the subterraneous 

 fleshy perianth, in which character and in 

 habit it is allied to Calypogeia. It is found 

 among mosses, especially in alpine districts. 



BIBL. Hook. Br. Fl. ii. pt. 1. 121 ; Br. 

 Jung. pi. 60 ; Ekart, Syn. Jung. pi. 1. fig. 6; 

 Endlicher, Gen. PI. Supp. 1. No. 472-23. 



SAC'CULUS, Gosse. A genus ofRota- 

 toria, of the family Ichthydina. 



Char. Eye single, frontal j body free from 

 hairs, and without a foot ; rotatory organ a 

 simple wreath ; alimentary canal very large ; 

 jaws set far forward, apparently consisting 

 of two delicate unequal lateral pieces, and 

 a slender central portion, very evanescent ; 

 eggs attached behind after deposition. 



8. viridis. Length 1-150" ; freshwater. 



BIBL. Gosse, Ann. N. H. 1851, viii. 198. 



SADLE'RIA, Kaulf. A genus of Blech- 

 neae (Polypodiaceous Ferns) . Two species ; 

 arborescent; Sandwich Islands. (Hooker, 

 Syn. Fil. 187.) 



SAGENEL'LA, Brady. A simple, 

 branching, Arenaceous Foraminifer, at- 

 tached to Nulli pores, forming a network 

 with its anastomosing branches (1-200" to 

 1-65" in diameter). Admiralty Islands. 

 (Brady, Qu. Jn. Mic. Sci. n. s. xix. 41.) 



SAGO. Farinas obtained from a variety 

 of tropical plants are known by this name ; 

 but the true East-Indian sagoes are ex- 

 tracted from the central part of the trunks 

 of Palm-trees belonging to the genus Sagus, 

 natives of the Moluccas. In PI. 46. fig' 23, 

 is figured the starch of a sago obtained 

 from the Museum at Kew; but it is un- 

 certain whether this is the produce of a 

 8agus ; its grains resemble those of some 

 East-Indian Arrow-roots (PI. 46. fio-. 18). 

 See STARCH. 



SAGRI'NA, D'Orb. (SAGRAINA, Reuss). 

 See UVIGERINA. 



SAL A 'CIA, Lamx. A genus of La- 

 foeidae, Hydroid Zoophytes. 



Char. Stem erect, composed of aggregated 

 tubes, branching, rooted. Cells cylindrical, 

 sessile, without operculum, adnate for the 

 greater part of their length, on all sides of 

 stem and branches in regular longitudinal 

 rows. Ovicells scattered on the stein and 

 branches. Polypes long, cylindrical, with 

 a conical proboscis. 



S. abietina. Deep water off Northumber- 

 land coast. (Hincks, Hyd. Zooph. 211 ) 



SALICINE. The alkaloid of the willow 

 and poplar. 



The so-called circular crystals of this 

 substance (PL 39. fig. 9) form a beautiful 

 polarizing object. The largest crystals are 

 obtained by fusion. 



SALICORNA'RIA, Cuv.-A genus of 

 Cheilostornatous Polyzoa. 



Char. Surface divided into rhomboidal 

 or hexagonal spaces by ridges surrounding 

 the cells ; avicularia disposed irregularly. 



