THE VICTORIAN NATURALIST, 139 



tinguished by its long creeping stems, which give off at intervals 

 bright-green, upright, cylindrical, branching fronds. They feel 

 like soft velvet, only rather slimy. Harvey says that their repro- 

 duction is still unknown. Although they have absolutely no 

 division walls in their structure, they have a system of vegetable 

 beams and rafters which keeps their outside walls in position. The 

 Codium has the same soft, slimy feel, and is green and cylindrical, 

 but there the likeness ceases, being multicellular, the inside of the 

 stems being solid. From the solid centre spring thousands of tiny 

 hairs like the pile of velvet ; between, or rather growing on these 

 hairs, or ramuli, as they are called, are thousands of zoospores from 

 which new plants arise. Another Caulerpa (very rare), C. sedioides, 

 was also found ; it consists of branching fronds bearing bright- 

 green air bladders. The tide was so very high that it prevented 

 the party from obtaining many specimens of really local plants 

 — these, of course, must be found growing on the rocks, or their 

 exact locality cannot be determined. It is to be hoped that 

 another excursion may be settled for some Saturday when a low 

 tide may be reckoned on, for the members of the party were 

 tantalized by seeing thousands of plants growing on the rocks, 

 but entirely beyond reach. Black Rock is evidently a well 

 chosen ground under favourable circumstances. It would be 

 very interesting to follow out the different families that grow in 

 pools left by the retiring waves, commencing with those that are 

 first uncovered, and in which will be found many kinds of green 

 seaweed (Chlorosperma). Gradually, as one explores seaward, the 

 green will be seen to give place to olive-green, brown, and even 

 almost black seaweeds. In the lowest tide pools, or under some 

 of the larger brown seaweeds, may be obtained a number of the 

 red seaweeds. However, our party had to content itself by 

 dragging out masses of seawrack, from amongst which quite a 

 number of good specimens were obtained. The delicate fronds 

 of Callithamnion Griffithsia, Areschougia, and Plocamium were 

 mixed up with great masses of different kinds of Fucacea. No 

 less than six of these last were obtained, including Sargassum, 

 Sierococcus, Cystophira, Hormosira, and Ecklonia. The broad, 

 serrated fronds of Ecklonia were especially noticeable. Other 

 brown seaweeds were Myriodesma, Haliseris, Myriocladia, and 

 Zonaria. A few pieces of the white, coral-like Amphora were 

 mixed up amongst the long branches of brown Cystophora, and 

 the serrated edges of a beautiful bright red Phacelocarpus were 

 entwined amongst the long, nearly black, grass-like fronds of 

 Melanthalia. A great number of leaf-like fronds were found, but 

 although somewhat resembling the smaller species of Lenormandia, 

 we were inclined to think that they belonged to some land plant. 

 Only one species of Gelidium was obtained ; this was a green 

 variety, G. y land u folium. It is particularly necessary to see if 



