192 DESCRIPTION OF BALLIA. 
vel subdichotomi, flexuosi, axillis acutis vel obtusis, erecti: 
superiores plus minusve divisi, sæpe in flabellam expansi, vel 
ramulos fasciculatos ex apicibus ferentes: rami omnes ramulis 
articulatis, distichis (vel raro tristichis), pluries. pinnatis, 
creberrime obsessi. — Ramuli (in circumscriptione) lineari- - 
lanceolati, bi-tripinnati, pinnis pinnulisque oppositis, creber- 
rimis; ramuli-ultimati-pinnati (vel plumule) quam rachide e 
quo oriunt multoties tenuiores, pinnulis creberrimis, contiguis, 
subulatis, acutis.. Pinnz et pinnule nunc tristiche. Articuli 
pinnarum sesqui-longiores; pinnularum diametrum squantes; - 
superiores breviores : articulus singulus apice concavus, bast 3 
convexus, superior in inferiorem insertus, e cellula unica — 
formatus, sacculam endochrome includens. Fructus: mass 4 
subglobosa vel oblonga, fusco-rubra, in apicibus sphacelatis 
rachidium ramulorum majorum et minorum immersa; apex 
fructifera nunc elongata, nune contracta. Color purpureo- 
roseus, pellucidus; marcescente in viridem, tandemque im e 
albo-luteum mutatus. Substantia caulium cartilaginea ; ramU- — 
lorum tenuis, corneo-membranacea, rigida, hyalina. © 
It will be at once perceived, that our plant has many po l 
in common with Sphacelaria, from which genus however, Í 
venture to pronounce it, according to the present views at 
systematic algologists, to. be abundantly distinct, and in this E 
opinion my friends Dr Greville and Mrs Griffiths concur. 4 
Unimportant as colour confessedly is in most classes of plants z 
it has been found to be a very correct indicator of affinity — 
among the Algz, and so constant that it has been made eei - 
basis of arrangement in the systems of Lamouroux, Agate): 
and their followers. Sphacelaria is a genus of the olivaceous : 
series; Ballia belongs to the florideous, in which it may stand — 
as the analogical representative of the former. But it is e = 
merely in colour that the latter differs; the substance of the — 
. frond, and the structure of the joints, present very striking 
distinctive characters; and the. opposite ramuli are very - 
unusual in Sphacelaria.. The subs tance of the lesser branches 
is of that peculiar, horny-membranous, hyaline nature; which 
distinguishes some tribes of zoophytes, and is found among t! 
