Plants in m. high n, urn ah ified, dimorphic. 



me nodulos upwards numerous green filatnents sparselj and dichoto 



mousl) branched and in Chlorodesmis comosd) <>r combined into stalked 



il.i 



onally forked, about i cm. long, 0.3 0.6 mm. thick, composed 

 : orticated, dichotomous filaments, expanding cuneatelj into 

 the 



1 2 cm. high, 1 1.5 cm. wide, green, sometimes proliferous 

 nposed of free, non-corticated filaments. 

 ts monostromatically arranged, subcontiguous, radiating from base to ciliaft 

 growing specimens emitting .1 few lateral branches, which creeping over 

 main filaments serve to bind them together. [Figs. 123— I2 5J- 



\\ 1 have nol seen this species, luit alter studying Ernst's long and well illustrated 



ivi are stronglj of opinion th.it the species is a good one and represents an ance- 



stral if F. petiolata (Udotea Desfontainii), a stage characterised by the absence of cortex 



from both stipes and frond. Further Ernst shews that the plant is dimorphic; besides the 



somewhat primitive stipitate frond, there is a caespitose growth of free filaments (Ernst loc. 



rit. taf. 7, fig. 6 = our fig. 123) which in our opinion so mucli resemble those of Chlorodesmis 



.'. .is to indicate indisputably the direct descent of F. minima from an ancestor of the 



Chlorodesmis type, in the same way as the survival of the Espera form shows the phylogenetic 



origin of Penicillus. Ernst's fig. 3] (basal filaments and rhizoids) and fig. 22 (torulose ascen- 



ding filament) are further indications of the close affinity of Flaöellaria minima with Chloro- 



ü (We copy in our figs. 123 — 125 some of Ernst's figures). We feel ourselves therefore 



('ompelled to remove from Udotea the two species U Desfontainii and ('. minima, and place 



them in a separate genus under the oldest available name - Flaöellaria Lamouroux (in Ann. 



Hist. Nat. Paris XX. 1813. p. 274). Further, according to the Vienna Code the binomial 



which must be adopted for i\ Desfontainii is Flaöellaria petiolata, Turra having published the 



Ulva petiolata in his Florae Italicae Prodromus 1758? p. 68 (1780 fide Pritzei 



It may be argued that F. minima is merely a growth form of F. petiolata, due to 



environment or to injury by marine animals, and that the poorly developed fronds are merely 



starved or regenerated states of the better developed F. petiolata. But even if this were so it 



: explain away the evident and close connection of these two plants with an ancestral 



ind their equally evident want of connection with Udotea javensis (Rhipidosiph 



all the other species of Udotea (which are all calcified, it must be remembered) can 



■ 



2. J iria petiolata Trevisan 



ttor p. 19. 



xnonymam Alcyonio innatam . . . . Zannichelli De Myriophyllo pelagico 1714.. 

 tab. 1. 



Marsilli Histoire physique tic la mer 1725 p. 64. tabb. VI, VII, figs. :j. 2$. 



