Considering the extent of interior known, at the present 

 day, in or about the parallel of Port Jackson, as also on the 

 north and south of that degree of latitude, the terrestrial part 

 of the family may be said to be comparatively rare in the 

 inland country. In their journeys through it at various sea- 

 sons, botanic travellers have observed but thirteen species; 

 and the whole of them are of genera, and indeed for the greater 

 part, of species, frequent on the sea coast at or near Sidney. 



These genera are Diuris, Orthoceras, Calochilus, Cala- 

 denia, Lyperanthus, Pterostylis, Gastrodia and Dipodium. 

 In fine, as a general remark on the geographical range of the 

 family in Australia, it may be observed, that as the terrestrial 

 species are greatly influenced by rains that may fall in the 

 season when they would under such favourable circumstances 

 appear above the soil, and as those whose localities are in- 

 land, beyond the range of those genial coast-showers which 

 occasionally fall in the midst of a long period of dry weather, 

 are wholly prevented from appearing above ground for two 

 or three years, to which extent the droughts in that country 

 have continued; these facts are sufficient to explain why it is 

 that this group also of the order in Australia, is so much 

 more abundant on its immediate shores, than it is either in 

 the up-country, as those parts of the colony a little distant 

 from the coast are termed, or the more remote interior. 



exceedingly thinly and generally lightly wooded, and thus its ample surface 

 being greatly exposed to the rays of the sun, an extreme dryness of atmosphere 

 is engendered, by no means favourable to the existence of a shade -loving 

 vegetation, affecting a lower temperature, but cooled simply by the surround- 

 ing air being, to a certain degree, permanently charged -with humidity. 



