Mary Sue Ittner msittner@mcn.org
Sun, 05 Dec 2004 22:18:19 PST
Dear All,

In the September 2004 Veld & Flora Cameron and Rhoda McMaster published an 
article: An assortment of Haemanthus: five species and various forms of 
this interesting bulbous plant from the Eastern Cape. Cameron has expanded 
this article for an introduction to the topic of the week. He has also 
provided 18 new pictures for the wiki of some of the species described in 
that article and this introduction. All of our messages have to be in text, 
but I have saved his Introduction, which will be in two parts since it is 
long, in htm format and will link it on the wiki Haemanthus page for those 
of you who might want to print it out with the formatting intact. Here is 
the first part:

Haemanthus L. (Amaryllidaceae) TOW

Confined to South Africa and Namibia, the 22 currently known Haemanthus 
species are characteristically fleshy, often hairy plants, well known for 
their compact, brush-like inflorescences. Their specialised fruits are 
berries which contain a few large, moisture-rich seeds. Bulbs of Haemanthus 
were amongst the first plants gathered at the Cape and subsequently 
cultivated in the gardens of Europe. The earliest known description 
appeared in 1605 where plants (probably H. coccineus and H. sanguineus) 
were given the phrase name Narcissus Africanus sive Narcissus exoticus. The 
name Haemanthus was first proposed by Hermann in 1687 and thereafter 
appeared in many publications in the form of Haemanthus africanus. Baker 
published a taxonomic treatment of Haemanthus in Flora Capensis (1896), 
which included Scadoxus. In a brief review of the genus by Friis and Norval 
in 1976, the generic limits of the Haemanthus were amended and the genus 
Scadoxus reinstated. As presently circumscribed, Haemanthus includes only 
species with true bulbs, distichous fleshy leaves and a chromosome 
complement of 16.

The last comprehensive taxanomic treatment of Haemanthus was by Dr Dierdré 
Snijman of the Compton Herbarium, Kirstenbosch, Cape Town, published in 
1984 (Journal of South African Botany, Supplementary Volume No. 12), from 
which much of the information in this introduction is taken. She lists 21 
species in this revision and subsequently described one further species 
(Haemanthus pauculifolius). Of the 22 species, 14 occur exclusively in the 
winter rainfall region with a concentration of species in the dry 
Namaqualand region of the North West Cape. Six species occur exclusively in 
the summer rainfall region and there are two species which overlap into 
both regions, namely H. coccineus which has the widest range extending from 
Namaqualand to the Keiskamma River in the Eastern Cape and H. albiflos 
which is a summer rainfall species, extending as far west as Still Bay in 
the winter rainfall region.

Most species bear two leaves each year. The shape, pubescence, markings and 
orientation are valuable taxinomically. In the evergreen species H. 
albiflos and H. deformis, leaves persist beyond a year, resulting in 4 to 6 
visible leaves. The majority of individuals in H. unifoliatus and H. 
nortieri and H. pauculifolius have only a solitary leaf, but in the latter 
species, being evergreen, the leaf persists and may exhibit two leaves. 
Haemanthus flowers are borne in an umbel surrounded by membranous to fleshy 
spathe valves, the position, number and texture of which is taxinomically 
important. The fruit is a globose to elliptical berry which when ripe is 
soft, pulpy and often translucent varying in colour  white, yellow, orange, 
red and various shades of pink, depending on the species. The seeds are 
succulent, smooth and greenish-white to wine red.

Dr Dee Snijman, in her article "What makes Southern Africa’s Amaryllidaceae 
special" in the IBSA Bulletin No. 42 (1994), describes the seed dispersal 
as follows: "When in fruit the scape of Haemanthus elongates and gradually 
flops to the ground. The funicle which holds the seed to the fruit wall 
produces copious mucilage, aiding germination by protecting the seed from 
desiccation. This mode of dispersal is thought to be one in which the seeds 
are shed in "safe-sites", namely patches close to the parents’ suitable 
habitat. This strategy maximises the suitability of the niche in which the 
seed is deposited which in turn maximises seedling survival. However, the 
species’ ability to spread is limited." It was always a puzzle to me how 
plants of H. humilis could become established on almost vertical places 
between the rock strata on cliffs where they grow. When handling ripe seed, 
we soon realised that this is due to fact that the seeds are connected to 
sticky threads that enable them to adhere to virtually any surface and, 
under favourable conditions they become rooted seedlings. This feature is 
probably common to other cliff growing species.

(to be continued)
Cameron McMaster
africanbulbs at haznet.co.za

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