69 



are restricted in their wanderings by the nature of the different 

 soils whic^ they encounter, and are largely influenced by cli- 

 mate and temperature. But the materials are not yet collected on 

 which may be founded a history of the movements of either our 

 Aliens or Natives. 



Another cause of the rapid dispersion of certain species may 

 be found in the fact that useful plants are introduced almost simul- 

 taneously at widely distant points. From these points their 

 descendants radiate, as from so many centres of creation, and 

 quickly occupy the ground. 



Other species again are restricted in an unaccountable manner 

 to single spots. Southport alone produces the commonest of all 

 English weeds, the Buttercup {Ranunculus hirsutus), where it was 

 found many years ago, but from whence, so far as I can learn, it 

 has never yet strayed. Southport also produces a common English 

 Grass, Hordeum pratense. At Circular Head, and nowhere else, 

 are associated the British Caucalis nodosa, and the more tender 

 Trifolium tomentosimi from Southern Europe. In like manner the 

 hardy Chenopodimn murale and the tender Lavatera hispida meet 

 together in the islands in Bass' Straits, and only in those islands ; 

 while the Crepis virens of Northern Europe appears to confine 

 itself to Deloraine, from whence it was sent me by our valued 

 friend, the Rev. J. E. Tenison- Woods, whose absence from our 

 meetings we must all deplore. 



The Order Compositse, of which the last-named plant is a member, 

 has furnished Tasmania with the greatest number of its aliens. 

 It is by far the largest of all the Natural Orders, embracing not 

 less than 10,000 species, adapted to live in every climate and on 

 every soil. Consequently in every quarter of the globe we may 

 expect to meet with an abundant supply of naturalised Composites. 

 Tasmania draws from this source 32 sjDecies, or one-fifth of the 

 whole of its alien flora. The family of the grasses comes next ; 

 of these we count up 29 immigrants. The leguminous, or beanlike, 

 plants furnish us with 15 species ; the Cruciferce, or cabbage tribe, 

 with 11 ; the CaryopJmfllece, or pinks, the Umbelliferce, or carrot 

 tribe, with 7 each. 



After these follow 26 Natural Orders of less importance, each 

 contributing their 2, or 3, or 4 strangers, until the whole number of 

 162 species is made up. 



It is not, of course, my intention to inflict upon you the names 

 of our numerous aliens, of which a classified list lies on the table. 



On the table also are specimens, dried and mounted, of all the 

 species which I have been able to secure. These amount to 138 

 out of the 162 ; which I beg the Society to accept, and to place in 

 the Museum. 



