GEPP—MARINE ALGA AND MARINE PHANEROGAMS. 395 
An interesting account of this species is given by Sauvageau (Biol. Trav. Lab. 
viii. pp. 66-81), to which our attention was drawn by Madame Weber van Bosse. 
The author there points out sundry errors made by J. G. Agardh in his ‘ Analecta 
Algologica,’ continuatio i. (1894) p. 11, in describing his new genus Gymnosorus, 
which is founded on the present species. J. G. Agardh separates Gymnosorus from 
Zonaria in the belief that the former possesses neither indusium nor paraphyses. 
Sauvageau, however, and, before him, H. M. Richards have seen the indusium, which 
Sauvageau describes in detail; and as regards the paraphyses he observed peculiar 
bodies which, though not typical paraphyses, are at least comparable with them. It 
is therefore obvious that the type of Gymnosorus must be excluded from that genus ; 
that is, Zonaria variegata resumes its old position. Sauvageau has closely studied 
the plant in the Canaries, and describes the manner in which the erect thallus grows 
out from the horizontal or creeping thallus, and points out its preference for shallow 
rock-pools, where it can creep over submerged surfaces near the brink of the pool. 
The normal form of the plant is the creeping rooting thallus; and the erect form is 
only found when some marginal part or parts of the growing thallus fail to find a 
suitable substratum to which they may attach themselves, and accordingly remain free, 
finally, after the death of the older creeping parts, assuming the appearance of an erect 
plant with a comparatively small base. 
The creeping vegetative thallus is figured in the account of the Marine Algze 
collected at the Maldive and Laccadive Islands by Mr. Stanley Gardiner, in Journ. 
Linn. Soc., Bot. xxxv. (1903) tab. 13. figs. 1-4, under the name Ralfsia ceylanica, Harv. 
This plant, previously undescribed, is, as we now see, nothing but a typical form of 
Zonaria variegata. 
Paprna, Adans. 
45. Padina Commersonii, Bory, Voy. ‘Coquille,’ Bot. i. (1826-8) p. 144, tab. 21. 
fig.2; De Toni, Syll. Alg. iii. (1895) p. 244. 
Seychelles: Praslin, on reefs exposed at dead low tide. 
Geogr. Distr. West Indies. Indian and Pacific Oceans. 
46. P. distromatica, Hauck, in Hedwigia, xxvi. (1887) p. 48; De Toni, Syll. Ale. 
iii. (1895) p. 244. 
Seychelles, on reefs exposed at dead low tide. 
Geogr. Distr. Somali coast. 
Hautseris, Targ.-Tozz. 
47. Haliseris Woodwardia, J. Ag. Spec. i. (1848) p. 116; De Toni, Syll. Alg. ii. 
(1895) p. 254. 
Seychelles, 44 fms.; Praslin reef. Amirante, below 20 fms. 
Geogr. Distr. Australia. Sarawak. China Sea. 
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