156 PARASITES ON NULLIPOK.E. 



beside another in globose masses, something like the 

 gills of a mushroom. Others are much more solid, and 

 resemble masses of smooth calcareous rock, here and 

 there rising into wart-like prominences ; and others 

 again are very much branched, like stony trees or 

 shrubs. When growing, the colour of the frond is more 

 or less of a livid purple, becoming, on the death of the 

 plant, of a brick-dust hue. Various others of the 

 smaller Algae, and a considerable number of marine 

 animals, may be collected on the Nullipore-banks. 

 Among the Alga? which especially frequent the Nulli- 

 pores, one of the most interesting is Padinellaparvula, 

 an olive, Lichenoid species, very frequently found at- 

 tached to various Nullipores. Polysiphonia parasitica, 

 P. subulifera, and P. furcellata, are also among the 

 rarities frequently found in this locality ; and the more 

 common plants are Rhodymenia bifida, It. ciliata and 

 broad varieties oiDictyota dickotoma. Among animals, 

 several of the Annelides, and some of the Naked Mol- 

 luscs, will reward the zoologist ; and the collector of 

 minute shells may secure several of the Rissoce on this 

 ground. Banks of Nullipores are, however, not very 

 prolific ; and though they afford sufficient interest for 

 a few hauls of the dredge, and are therefore always 

 worth a visit, their variety is soon exhausted, and the 

 dredger soon satiated. Very frequently, also, a large 

 portion of the bank consists of dead fronds, and these 

 yield little to interest the explorer. 



A more fertile ground for the dredger is found on the 

 borders of scallop- or oyster-banks, the former being 

 generally at a depth below the level at which most 

 marine plants vegetate, though an occasional straggler 



