. § RULE FOR DETECTING SPIRAL ARRANGEMENT. 
deorsum dilatata, antheris ovatis violaeeis. Persia borealis prope 
pomeee uh 
20*. H. (Betzevart1a) syriicus, Baker—Fellevallia syriaca, Her- 
bert Bot. Res. 1844 Mise., p. 89.—Folia plura glauca lanceolata 
8 
albescentibus apice subrufescentibus equilongo. Filamenta alba basi 
complanata, antheris fus sco-purpureis. Ex Oriente (loco speciali 
ignoto). Fox-Strangways in Hort. Herbert. Péttinris not distinct 
from ieee 
22*- ia ae Oxivrert, Baker, n sp.—Bulbus ovoideus 
eorsum lax : 
libus ddocndeiins Bracteze minute deltoidesw. Perianthium 
tubulosum 5-54 lin. longum, in. crassum, siccitate fuscum, 
dentibus oblongo-déltnidete t tubo triplo brevioribus. Stamina ex fauce 
uniseriata, filamentis linearibus 1 lin. longis. In valle fluminis 
Tigris inter Mossul et Bagdat. abs in Herb. D 
. (Betrevatria) caprratus, Baker, n.sp. —Bulbus ovoideus 
- - lin. crassus. Folia a bina, ‘eo scapi amplectentia lorata falcata 
oso-herbacea 38-34 poll. longa in. lata, venis immersis, apice 
deltoideis leviter cucullatis, rrareinibus minute ciliatis. Scapus 3 
thium tubulosum 3-34 lin. longum, 13 lin. crassum, siccitate fuscum 
segmentis ovato-deltoideis tubo triplo brevioribus. Stamina ad faucem 
uniseriata, filamentis lanceolatis, antheris minutis oblongis czruleo- 
— - Aes (loco speciali ignoto). Olivier! in a Hes, C. 
rapoxus, Baker, non Fisch. & Meyer.—Must now be 
cle H. lsu, Baker. 
crn1aTus.—Add synonym H., patulus, Bert. Nov. Comm. 
ey pia: vi; 430, Walp. Ann. i., 854. 
28. H. GLAUcuS, Baker.—Add synonym H. purpureus, Griffith 
re 275, Notule, p. 242. 
ELEMENTARY PROOF OF THE RULE FOR DETECTING 
SPIRAL ARRANGEMENT. 
Br F. E. Krrewensr, F.L.S.. 
Wuen the subject of spiral arrangements is taken in our text-books, 
the rules by which an intricate spiral arrangement can be detected by 
means of the approximating secondary spirals are given without any 
demonstration. 
