ALGLE OR SEA-WEEDS. 157 



species of Sargassum are found on these coasts, and some of the 

 rarer ones are figured in Harvey's Phycologia. The common 

 species S. bacciferum (so termed from its berry -like vesicles which 

 have sometimes been called sea-grapes) may often be collected, 

 and indeed it has been found almost at the head of the Parramatta 

 River, whither it had been conveyed by the tide. This species is the 

 one alluded to in Robertson's History of America : " When about 

 400 leagues to the West of the Canaries, Columbus found the 

 the sea so covered with weeds that it resembled a meadow of vast 

 extent, and in some places they were so thick as to retard the 

 motion of the vessels. This strange appearance occasioned new 

 alarm and disquiet to the sailors. They imagined that they were 

 now arrived at the utmost boundary of the navigable ocean, that 

 these floating weeds would obstruct their further progress, and 

 concealed dangerous rocks, or some large tract of land which had 

 sunk, they knew not how, in that place. Columbus endeavoured 

 to persuade them that what had alarmed, ought rather to have 

 encouraged them, and was to be considered as a sign of approach- 

 ing land." I have instanced S. bacciferum as being likely to 

 catch the eye of the observer on account of its frequent occur- 

 rence ; but other species, particularly & vulgare, S. ligulatum, S. 

 Jilifolium, fyc., are often found on the eastern shores of Australia. 

 The genus Cystopliora is peculiar to these coasts, and according 

 to Harvey, represents Cystoseira of the Northern Hemisphere, 

 differing from that genus chiefly in the position of the receptacles. 

 In Cystoseira the air-vessels are arranged within the substance of 

 the branch-like leaves, whereas in Gystoplwra, they are stipitate 

 and rarely absent. In Sargassum the receptacles are mostly ax- 

 illary in racemes, whereas in Cystophora they are pod-like, torulose 

 or moniliform, developed in the ramuli * C. spartioides and C. 

 platyloUum, as well as other species, occur frequently near Sydney, 

 and C. lotryocystis was discovered by Dr. Mueller at Port Phillip. 

 Phi/llospora comosa, or Macrocystis comosa, may often be found at 

 Manly Beach. It has a stem flat, smooth, and pinuately branched ; 

 leaves marginal, lanceolate-linear, attenuate, distantly toothed ; 

 vesicles elliptical, leaf-bearing. This is one of the largest of our 

 sea-weeds, and is allied to Macrocystis luxurians, which, Dr. 

 Hooker says, in its horizontal growth at the surface of the ocean, 

 ranges between 200 and 700 feet in length, whilst at the Falkland 



