ATJSTBALIAN FEKtfS 71 



mentions it also as one of the ferns in the Chatham Islands. The 

 fronds vary in form, being sometimes linear and sometimes pin- 

 natisected. P. rugosulum is much more divided than the preced- 

 ing species, and it has a rough and somewhat wrinkled appear- 

 ance. The fronds vary in size from a few inches to three or four 

 feet in length, and are tripinnate. Dr. Mueller has justly re- 

 marked that some of the varieties bear great resemblance to the 

 exindusiate form of NepJirodium velutinum, and others to Hypole- 

 pis tenuifoUa. Mr. Macgillivray has lately collected some speci- 

 mens at the Clarence, which at first sight I was disposed to con- 

 sider as varieties of P. nujosiihim ; but subsequent examination, 

 and the opinion expressed by Dr. Mueller in reference to one of 

 these forms, induce me to think that one of the specimens is Hy- 

 polepis, and the other a Nephrodium (A 7 ", tenerum ?) from which 

 the indusia have fallen. Some time since I met with a great 

 quantity of N. decompositum in a similar state, and it was not un- 

 til I had examined numerous fronds, that I succeeded in finding 

 a young plant with the indusia visible on it. In some varieties 

 of Nephrodium,ihein(lu.smm is of a very fugitive character, and hence 

 the possibility of referring to Polypodium, species which do not 

 properly belong to that genus. P. rugosulum, in different va- 

 rieties, is widely distributed not only in Australia, New Zealand, 

 and the islands of the Pacific, but also in India, South America, 

 &c. Sir William Hooker includes the Norfolk Island Cheilanthes 

 Dicksonioides or Hypolepis Didcsonioides amongst the varieties of 

 this species. In the second section of the genus the veins are 

 more or less anastomosing or netted, and by some botanists the 

 species are referred to eight different genera. The first Austra- 

 lian species is P. pceciloplilebiuni (so called from the varying veins 

 on the same frond), which was collected on Dunk Island, north- 

 east coast of Australia, by Mr. Macgillivray. Whether this is 

 really a Polypodium or not seems rather uncertain, but as far as 

 can be determined from the venation, the species is correctly 

 placed. Near this fern must be considered the CampyloneMron 

 which Dr. Mueller discovered on the north-west coast of this 

 continent (see " Botanical Report on the North Australian Ex- 

 pedition under the command of A. C. Gregory, Esq"). The 

 genus Campyloneuron was established from the peculiarity of the 

 venation, the primary veins being pinnate, parallel, and connected 



