Ixxvil The Transactions of the South African Philosophical Society 
parallel wings on /Pterodiscus speciosus, and two opposite wings on the 
achenes of the disc flowers of Dimorphotheca. There are three wings on 
the achenes of numerous species of Tripteris, and on the fruits of Begonia, 
Portulacaria afra, Dodonea Thunbergu, Oxygonum alatum ; four wings on 
Zygophyllum, Combretum primigenum and other species of Combretum ; 
five wings surrounded by the finely-lacerated calyx on Lwederitzia pen- 
taptera from Damaraland ; and six wings, with some additional crests, 
on the pretty Zriaspis hypericoides in Southern Bechuanaland. The 
fruitlets of Chenopodiaces, ¢.g., Atriplex, are provided with a mem- 
branous pericarp and more or less altered bracts, and most Amarantaceze 
are similarly equipped. The nuts of Welwitschia mirabilis use the 
persistent scales of the cone as wings, just like the smaller fruit of the 
hop; the fruit of Polygala myrtifolia retains two sepals as wings, and 
the capsule of G'rielum is crowned by the fine membranous calyx lobes. 
Several genera of Composite possess a scaly pappus which often crowns 
the achenes like a large umbrella, ¢.9., Sphenogyne, Ursinia, Arctotis, 
Stobeea, Berckheya, Haplocarpha. 
Although wings may appear to be the best contrivance for the 
utilization of the wind as motive power, on closer observation one finds 
that hairs are quite as effective, especially for small seeds. They cover 
either the whole seed or fruit, or form a tuft at their end. The seeds 
of Lriospermum and of several South African species of Hibiscus resemble 
those of the cotton plant, and the seeds of willows are excellent flyers, 
being provided with a hairy arillus. The achenes of the composites are 
adapted to their aerial journey in many ways. Some, e.g., Matricaria, 
Gamolepis, Artenusia afra, do not possess any appendages, being so small 
and light that the wind easily carries them for some distance ; others 
have wings as described before, and some others are hairy, e.g., Arctotis, 
Leptothamnus, Geigeria, or thickly clothed with wool, e¢.g., Tarchonanthus 
camphoratus, a shrub of wide occurrence, Cryptostemma calendulaceum, 
and Lasiospermum radiatum, two common weeds, and the numerous 
species of Hriocephalus, Gazana and Heterolepis. 
More than 1000 of our composites are provided with a pappus of 
hairs or bristles, such as is well known on the common everlasting 
Helichrysum vestitum. ‘The tuft of hairs at the top of the achene spreads 
its rays only in dry weather, and it fulfils its function so excellently 
that on sunny days one often sees the little fruitlets rise from the 
capitulum and sally out into the air, although not a breath of wind can 
be noticed. On the common dandelion (Taraxacum), the sow-thistle 
(Sonchus) and Hieracium, the pappus is provided with a stalk forming an 
extremely effective and beautiful parachute, by means of which the 
achenes sail through the air with the help of the slightest breeze. 
But not all our composites depend upon the agency of the wind for 
