201 
Origin and Development of the Composites. 
general account (I, 7, p. 572), but laid great stress on the colonising 
powers of the Composite apart from their dispersal mechanisms. 
Wallace (41) explains the anomalous distribution of certain Com¬ 
posite by their “great powers of dispersal,” and in Chap. XXIII 
gives some detail of the general migration from north to south 
along the mountain ranges. More recent observations by Guppy 
(21-22) and Praeger (30) emphasise the importance of ocean 
currents and birds as means of dispersal. 
A curious point is raised in the consideration of the dispersal of 
the radiate variety of Senecio vulgaris. Professor Trow informs me 
that although it is possible that the radiate character was introduced 
into Great Britain from the Channel Islands it would be more correct 
to speak of the spread of the character “ radiate” than of the radiate 
variety. The records of radiate groundsels are records of the 
character but are not necessarily records of the same variety. 
Dispersal by Animals. 
Dispersal by birds for comparatively long distances is given 
by Darwin (II, 16), Wallace (41), Hemsley (23), Guppy (21), 
Praeger (30) and others. The fruits during dispersal may be 
either inside the bird (in the crop or elsewhere) or outside the bird 
amongst its feathers or among the mud which occasionally adheres 
to the feet. 
Adherence of the fruit may be obtained by glandular structures, 
as in Adenostemma, Siegesbeckia and Wulffia (V, 30; IV, 98) or 
by mucilaginous pericarps, as in Rutidosis (V, 14), Chrysanthemum 
Fontanesii, Rtickeria and Trichocline (V, 32), and also in Chrys¬ 
anthemum multicaule as observed by the writer. Adherence may 
be obtained also by hooks, as in many genera ; the hooks being on 
the involucre, as in Arctium and Xanthium, or on the pappus, as in 
Bidens. These cases and several others are mentioned by De 
Candolle (11), Hildebrand (V, 30-32), Kronfeld (VII, 3), Huth 
(V, 41) and others. 
Dispersal by man has been mentioned only in passing by most 
botanists, but is the subject of a paper by Thellung (34) who 
mentions a number of Composite which have been dispersed as 
weeds or as horticultural plants. This rather neglected branch 
of fruit dispersal is most interesting on account of the many 
traditions with which it is connected, such as the reputed introduc¬ 
tion of “Stinking Willie” ( Senecio jfacobcea) into Scotland in 
the fodder of the German cavalry used by William, Duke of 
