Ile J: G. Agardh. 
vavit, fustus eam descripsit his verbis: ,Fronds at first globose, like tubers, 
heaped together, hollow and empty or filled with sea water, attached to 
the rock and to each other by a few short, rooting processes; at length 
irregularly torn and then forming expanded, cartilagimous or skin-like 
coarsely reticulated membranes. The membrane 18 wholly composed of a 
single layer of large, globose, or by mutual compression hexagonal cells, 
which closely cohere by their sides, leaving the convex ends of the cell 
free, and these form the surface of the membrane”. Quam eximie his 
verbis tum forma exterior frondis evolute, tum structura membrane sub 
stadio adultiore descripte censeantur, tamen veram evolutionis normam 
hac descriptione interpretatam fuisse vix putarem. Sequentia observare 
credidi. 
Sub statu maxime infantili frondem, 2—3 lineas longam, vidi tubu- 
losam (Tab. 11 fig. 1) et forma cylindraceam, deorsum prolongatam in 
radiculam brevissimam, strictura parum conspicua sub-separatam; superiore 
parte frondis minute nondum diaphragmatibus in cellulas subdivisa. Or- 
gana, poros &emulantia, que in adultiore fronde secus diaphragmata cellu- 
larum disponuntur, per totam longitudinem frondis tubulose presentia 
vidi; hinc forsan "conjicere liceat hanc quoque fieri in cellulas gquasdam 
longitudinaliter superpositas divisam; revera gquoque in nonnullis specimi- 
nibus adultioribus (ultra pollicaribus) observavi frondem rotundatam deor- 
sum continuari in cellulas paucas, articulatim superpositas, 2-—3, que quasi 
stipite brevissimo frondem globosam sustinent. Nescio an assumere lice- 
ret hec cylindracea initia aliquando magis evoluta fieri, et formam a 
Montagne descriptam, quam speciem propriam consideravit, ejusmodi sta- 
tum evolutionis referre. Ut plurimum vero frondem parte sua inferiore 
supra rupes expansam esse, et ex parte dilatata inferiore numerosas agere 
radiculas filiformes et tubulosas, satis constat. Quamquam frondem infan- 
tilem supra descriptam, nunc superne vesiculoso-infiatam observaverim, 
tamen formationem cellularum initialium observare mihi non contigit. 
Plantam paulo magis evolutam, at adhuc juvenilem, magnitudine dru- 
pam: minorem Cerasi circiter equantem, vidi totam cellulosam et solidam ; 
nimirum non tantum extrorsum in cellulas plurimas minores subdivisam, 
sed quoque in interiore sua parte cellulis numerosis compositam. CeNulas 
interiores paulo majores et quoquoversum angulatas dicerem; ceeterum 
