254 PROCEEDINGS OF SECTION D- 



rather an Iris in which the primordia of the floral leaves have failed 

 to continue their coalescence with the ovarian wall. 



A truly remarkable piece of distribution is the presence in 

 southern Tasmania of a Thismia. It is strange that a member of 

 an otherwise tropical genus should be found here at all, and that 

 it should be so well adapted that it has been gathered at an elevation 

 exceeding two thousand feet ; it is still more remarkable that it has 

 not been found in Australia. This is possibly an oversight, but if 

 at all common on the mainland it should certainly have been 

 gathered before this. 



The Coniferae are made up mainly of ancient remnants, most 

 of which are endemic. DacrydiitmFranklinii has relatives in New 

 Zealand and South America, and the monotypic Pherosphcera is. 

 sufficiently close to this genus that it may well be considered a local 

 off-shoot. Phyllocladus and Podocarpiis have a somewhat similar 

 distribution, and it is possibly reasonable to expect they had a 

 similar line of migi'ation, but Microcachrys is alone. Though like- 

 these others it is a Taxad, it appears to have no relative to suggest 

 whence it came. It is placed nearest Saxegothisa of South America, 

 but the affinity is distant. 



Fitzroya has but two species, one in Tasmania, the other in 

 South America. 



The genus Arthrotaxis is confined to Tasmania and is a remnant 

 of the Taxodineae that possibly had an equatorial distribution. It 

 probably owes its survival to some of the western mountains of 

 Tasmania, having escaped submersion. Tasmania is but a small 

 island, and it would be difficult to account otherwise for so many 

 remnants being confined to its western half when other localities 

 appear to afford climatic conditions equally favourable to their 

 existence. 



6.— AUSTRALIAN AND SOUTH SEA ISLAND STICTACE^E. 



By EDWIN CHEEL, Botmikal Assistant, Xntioiial Heibaniim, Sydney. 



PART I. 



Introduction. 



The family of plants known as Stictaceae comprise some of the 

 largest and most beautiful of the foliaceous species of the Lichen 

 Flora, and according to the most modern system of classification 

 are divided into two well-marked genera, namely, Loharia and 

 Sticta. 



Of these two genera there are recorded in the now overwhelm- 

 ing and ever-increasing mass of lichenological literature the names 

 of upwards of 400 species or sub-species and varieties. Of this 

 number there are already recorded as having been found in Aus- 

 tralia, New Zealand and the South Sea Islands the names of about 

 175 species. 



