BOU 



BRA 



Group 6.— Glumos^. Bract scale-like, glumaceous, imbricated, in the room of a 

 calyx. 



Graminaceae. Desvauxiaceae. 

 Cyperaceae. Restiaceae. Xyridaceae. 



Class III.— AcROGENS, Cryptogamic, or Flowerless Plants. 



Plants usually composed of cellular tissue only. Stem, when such exists, increasing 

 by extension of its point. Reproduction taking place either by spores inclosed in 

 thecce, or imbedded in the substance of the plant. Germination occurring at any part 

 of the surface of the spore. 

 Sub-class 1. — JEtheogamous. Plants furnished with air-vessels and stomates. 



Filices. Marsiliaceae. Lycopodiaceae. 



Equisetaceas. Salviniaceae. Marchantiacese. Jungermanniaceae, 

 Sub-class 2. — Amphigamous. Plants having neither air-vessels nor stomates. 



Characeae. Andraeaceae. Fungaceae. 



Musci. Lichenaceae. Algaceae. 



BOTANY BAY RESIN. An aro- 

 matic resin which exudes from the trunk 

 of the Acarois resinifera of New Hol- 

 land. 



BOTHRE'NCHYMA {^69pof, a pit, 

 cYX^Mcii enchyma). A name recently ap- 

 plied in Botany to the pitted tissue or 

 dotted ducts of former writers, the appear- 

 ance of these tubes being occasioned by 

 the presence of little pits sunk in their 

 walls. It is either articulated or conti- 

 nuous. 



BOTRY'LLARI^ {/36rpvs, a bunch of 

 grapes). A group of the tunicated mol- 

 lusca, in which the individuals con- 

 sist of small ovoid bodies, which attach 

 themselves to sea-weed or other sub- 

 stances in regular bunches, arranged 

 like the rays of a star around a common 

 centre. 



BOTRY'LLI (/36tpi/?, a bunch of 

 grapes). A little cluster of berry-shaped 

 bodies. 



BOTRYOI'DAL (y36Tpv9, a bunch of 

 grapes, et^of, likeness). Clustered, like 

 a bunch of grapes. 



BO'TRYOLITE {^erpvs, a bunch of 

 grapes, KiOos, a stone). A mineral oc- 

 curring in botryoidal masses, in a bed of 

 gneiss near Arendahl in Norway, and 

 considered by some writers as a variety 

 of datholite. Its basis is boron. 



BOULDERS. Erratic Blocks. A 

 provincial term for large rounded blocks 

 of stone lying on the surface of the 

 ground, or sometimes imbedded in loose 

 soil, different in composition from the 

 rocks in their vicinity ; hence it appears 

 that they have been transported from a 

 distance. 



BOURGEON; BOUTON. Terms ap- 

 plied by French botanists to the leaf-bud 

 60 



and the flower-bud, respectively, of Eng- 

 lish writers. 



BOUSTROPHE'DON (/3ovf, an ox, 

 o-Tpe0a), to turn). A term descriptive of 

 a mode of writing alternately from left to 

 right and from right to left, from its re- 

 semblance to the mode of making fur- 

 rows in ploughing a field. Some speci- 

 mens occur among the Arundelian 

 marbles at Oxford. 



BOVEY COAL. Brown Coal. A va- 

 riety of coal found at Bovey Heathfield, 

 near Exeter. It consists of wood pene- 

 trated with petroleum, sometimes con- 

 taining pyrites, alum, and vitriol. 



BO'VIDiE (bos, bovis, an ox). The 

 Ox tribe ; a family of the Ruminantia, 

 in which the horns are directed upwards 

 and forwards, and increase by layers 

 during life. 



BOYLE'S FUMING LIQUOR. Hy- 

 dro-sulphuret of ammonia, or volatile 

 liver of sulphur. See Fuming Liquor. 



BRA'CCATE (bracca, breeches). A 

 term applied to the feet of birds when 

 concealed by long feathers descending 

 from the tibia. 



BRACHELY'TRA (/3paxv9, short, ^\v- 

 rpov, a wing-case). A family of the pen- 

 tamerous Coleoptera, characterized by the 

 presence of four palpi, and by the short- 

 ness of the wing-cases. The staphylinus 

 is the only genus of the family. 



BRA'CHIATE {brachium, an arm). 

 A term applied in Botany to branches 

 which diverge nearly at right angles from 

 the stem. 



BRACHIO'PODA {ppayioiv, an arm, 

 TTouf, TTo^or, a foot). A division of the 

 Mollusca, so named by Cuvier from their 

 having two long spiral arms placed on 

 each side of the mouth, which in many 



