156 THE PLANT WORLD. 



cious heads ; the male and the female heads being alike discoid, 

 save that the male heads have sometimes a ray of fertile flowers. 



Sir J. D. Hooker remarked anent such forms as Chillotricli- 

 iinn- and Senecio, that radiate flower heads often affect a moist 

 climate, whilst dry climates are aj^t to produce discoid heads. 



The Aster tribe ends with the great genus Bacchcwis, whose 

 species are normally dioecious, most frequently frutescent, and 

 often with vringed stems. In South America occur 300 species 

 of them, of which 31 are in Patagonia. Thev are troublesome 

 to botanists from the circumstance that many sj>ecies are known 

 only from one sex, and usually the specific characters must be 

 fixed chiefly from the leaves alone. Barrliaris juncea Desf. has 

 a tall, rushlikc stem, and few very strict linear leaves, and B. 

 urviUeana Brongn. with opposite leaves, was figiired, but never 

 described; the figure has Iwen obtained for our Flora (plate 

 xxxi) through the courtesv of Professor F. E. Llovd. 



It is strange that dioecious plants should be so flourishing, 

 as if the separation of sexes rendered them more prolific. 



The Inuloidese, or Everlastings, are remarkable for having 

 their anthers both tailed and appendaged, and their styles not 

 appendaged ; and for their small heads, often without rays. They 

 are mainly an old world group, and some are interesting for giv- 

 ing evidence in favor of a former land-connection between Aus- 

 tralia and Africa. Some sub-tribes or genera are confined to 

 America; thus Tessaria is in California and Xorth Patagonia, 

 extending along the Andes. Chevreulia (with long achenial 

 beak), is confined to South America (with a species in Falkland 

 Islands, and one in Tristan) ; and Facelis, achenes beakless, is 

 confined to the Andes, and Xorth Patagonia. Psilocarpliits 

 reaches from California to Patagonia; and Micropsis, an Old 

 World genus, has a species 21. nana DC. in Chili and ]^orth Pat- 

 agonia. Adenocaulon is another case of generic discontinuity; 

 one species being in Asia and iSTorth America, and A. chilense 

 Less, being in Chile-Patagonia. 



(To he continued.) 



