DESCRIPTIONS OF N.Z. FERNS. 125 



ASPLENIUM UMBROSUM. (As-ple-ne-um Um-bro-sum.) 



PLATES v., No. 2, and XXIX., No. 4. 



This very handsome fern is also called " Asplenium Australe," " Asplenium 

 Brownii," Asplenium physosorus," " AUantodia Australis," and " Allantodia tenera," 

 the latter name from the Greek word allantos, a sausage, referring to the curved form 

 of the sori, and the manner in which they swell up as the capsules grow, until at 

 length they burst open along the edge farthest from the vein. The fern is found in 

 the Northern Hemisphere, from Madeira and the Azores and Canary Islands to 

 Ceylon and Java, and on the Himalayas it ascends to 6000 or 8000 feet. In 

 America it occurs in Ecuador and Peru, and in the southern part of the Eastern 

 Hemisphere it extends to Australia, Tasmania, and New Zealand. It is tolerably 

 abundant from Auckland northwards, occurs locally southward to Cook's Straits, and 

 has been gathered at Nelson ; but apparently nowhere farther south. It grows in rich 

 deep alluvial soil, in warm damp places, but not in deep shade. Under favourable 

 conditions it will grow five feet high, with fronds two feet or more in breadth ; but 

 varies so much in size and form that it is not easy to say what is its normal type. I 

 will, therefore, take the largest that I know, which occurs at Waikato, Upper Wan^anui, 

 and Rangitikei, and probably elsewhere also. The rhizome is stout, and slightlv 

 creeping, and bears a crown of few fronds. Stipes long, stout, erect, scaly at base, 

 smooth above, brown or brownish green. Rachis same colour, and smooth. Frond 

 broadly deltoid, tripinnate bplow, bipinnate above. The pinnules are stalked below 

 and sessile above, long-oval, with edges cut into rather deep rounded lobes. Sori 

 numerous, and when fully developed almost covering the under surface of the pinnules. 

 Involucres membranous, white, and much swollen, till they burst open ; after which 

 they are almost hidden by the capsules. Colour dark glossy green ; texture usually 

 almost membranous but sometimes harsh, and venation distinft. 



Var. parvifolium occurs near Auckland and at Taranaki. It is similar to the 

 above, but rarely exceeds three feet high, and its foliage is very much smaller. The 

 sori too are far less numerous, and do not cover the pinnules in the same way. To 

 my fancy it is the prettiest form of any ; and I noticed that it was preferred to the 

 other forms, as a pot-plant, by fern-cultivators at Auckland. In tact, I scarcelv saw 

 any plants of the larger kinds, except in regular ferneries. 



Var. hians (Plate XXIX., No. 4), which occurs in Australia and South America, 

 is, I believe, only found in New Zealand, at Wanganui. It is a coarse broad-foliaged 

 form, three feet to five feet high, with its pinnules widened at the base, falcate i^ 

 shape, and cut into deep rounded or pointed lobes. The sori are tolerably numerous 

 but never cover the under-surface of the pinnules, and towards the base of the frond 

 they sometimes occur on both sides of a vein, which causes the plant to be classed in 

 the sub-genus Diplazium in the Synopsis. From having grown it for many years, 



