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is referred to by Hilliard & Burtt (1971) as S. aff. michelmorei.
Streptocarpus michelmorei is a Zimbabweari species; the M.alawi plants
differ in fairly minor ways. It is unifoliate, with deep blue-violet
flowers which are sometimes whitish or with a yellow bar in the
throat. I first saw plants growing on the shady side of rocks at the
edge of a forest; inside the forest it grew epiphytically on tree-trunks,
on fallen logs and again on mossy rocks. Apparently it grows only in
and around Chimaliro Forest on the North Viphya, an inaccessible
area made more so by the fact that, to reach it, one has to drive
through an army firing range. This gives splendid protection;
elsewhere there is the usual deforestation but Ghimaliro, so far, is
safe.
REFERENCE AND BIBLIOGRAPHY
Hilliard, 0. M. & Burtt, B. L. (1971). Streptocarpus. An African Plant Study.
University ofNatal Press, Pietermaritzburg, South Africa.
(1986). Studies in the Gesneriaceae of the Old World. XLIX. Notes
Roy. Bot. Card. Edinburgh 43(2): 229-232.
Moriarty, A. (1975). Wild Flowers of Malawi. Purnell, Gapetown.
PLANTS IN PERIL, 20: HILDEGARDIA
Martin Cheek and Greg Leach
It is fortunate that few of the tree genera widespread through the
tropics can yet be said to be endangered in the wild, but Hildegardia
Schott & Endl. in the Sterculiaceae certainly seems to be such.
Named in 1832 after Hildegard, the eleventh-century German
abbess and mystic, the 'Sybil of the Rhine', 11 species of Hildegardia
are recognized, one from Cuba, three each from Africa and Mada-
gascar and one each from India, the Philippines, Indonesia and
Australia. They are usually tall, deciduous trees of well-drained
areas, often growing on rocky hills. Their trunks have a smooth, thin
bark which smells unpleasant and exudes a gum when wounded.
Most species have heart-shaped leaves and bear a profusion of
spectacular orange-red, kalanchoe-like flowers when leafless. These
are followed by strange, inflated, winged fruits enclosing one or two
seeds. It is the features of the fruits that separate the genus from
allied genera, such as Firmiana Marsili, and from Sterculia L., another
panlropical tree genus from which the family takes its name.
© Bcntham-Moxon Trust 1994. Published by Blackwcll Publishers, 108 Cowlcy Road,
Oxford 0X4 1JF, UK and 238 Main Street, Cambridge, MA 02142, USA.
Members of the Sterculiaceae are rarely seen outside the tropics,
apart from Fremontodendron Goville. However the South American
genus Theobroma L. is well known as the source of chocolate and the
African genus Cola Schott & Endl. provides the flavouring of the
eponymous beverage.
Our interest in this Uttle-studied genus was sparked-off by the
arrival of a specimen from Kakadu National Park in the Northern
Territory of Australia. The collection had been tentatively identified
by the local herbarium as Hildegardia, although the genus was
hitherto unknown from that continent. With the aid of the immense
resources of the Kew Herbarium, we were able to confirm this
beyond doubt and show that it was a new species, which we named
H. australiensis G.J. Leach & Cheek (Cheek & Leach, 1991). It is
distinct from H. sundaica Kosterm., its neighbour across the Timor
Sea in Indonesian Sumbawa. In the course of the investigation it was
revealed that most of the species of Hildegardia were known
historically from only one or two sites, sometimes from only one or
two collections, and that there were no recent reports of several
species in recent decades. This seemed to us an unusual case of a
widespread medium-sized genus of trees with perhaps most species
being vulnerable to extinction, and we were prompted to draw
attention to it by writing this article.
To ensure the long-term survival of H. australiensis will require
careful management. Our discovery that the Kakadu trees repre-
sented a new species prompted more visits to the area by local
Australian collectors who found that the species was restricted to
two populations. At the type locality several hundred trees of
varying ages were present. The nearby second population appears to
consist of only a few plants. The main population is only two km
from a local landmark, Coronation Hill.
Coronation Hill lies at the heart of one of the most heated
environmental issues being debated in Australia today, ranking with
concerns about the exploitation of the Antarctic. This is representa-
tive of the increasingly frequent clashes between commercial and
environmental interest groups. Estimated to be one of the richest
gold, palladium and platinum ore deposits in the Australian
continent, there is understandably a strong lobby in favour of the
granting of governmental approval of mining proposals for Corona-
tion Hill. Coronation Hill lies at the head-waters of the South
Alligator River, within the Kakadu National Park. The lower reaches
© Bentham-Moxon Trust 1994. 89
Sa^DS^?EAh^ ^Bl c^wayvlew^f frult- x }•' C^o-ring
h, x 1; u, flower, X 6; E, hairs from outside ofcalyx;X 60. Draw"nby'Ma'AFoZrc^Ie
90
© Bentham-Moxon Trust 1994.
of the river form an extensive flood-plain system which has received
World Heritage Status. The area around Coronation Hill is also of
considerable spiritual significance to the traditional Aboriginal
landowners. A cyanide extraction process to be employed in the
mining operations could prove extremely toxic to all life downstream
of the mining site. Should proposals go ahead, the mining could
result in serious pollution and disturbance of the Park, and the
possible extinction in the wild of the major population of H. aus-
traliensis. To date this species has not been introduced into cultiva-
tion.
Less detailed population data are available for H. sundaica.
Growing only in Sumbawa in the Lesser Sunda group, it is known
from only two collections. The first was made in the 1950s, and is in
fruit, the second is in flower. According to its original collector,
A. J. G. H. Kostermans ofBogor, now in his eighties, he was unable
to relocate any trees at the type locality when he last revisited the
site; nor is it known in cultivation. It was described as common at the
site of the second collection made in 1961, but the species has not
been recollected since.
The most poorly known of all Hildegardia species, H. merrittii
(Merr.) Kosterm., is known from a single fruiting collection made in
the 1930s from the island ofMindoro in the Philippines. We wrote to
the National Herbarium of that country, hoping to obtain some
information and more recently collected material of this species, but
learnt only that this species has yet to be rediscovered (Domingo
Madulid, pers. comm.).
The Indian species, H. populifolia Schott & Endl., on which the
genus is based, is a native of the western Deccan peninsula. Precise,
modern information on the distribution and states of populations of
this species is hard to come by, and our studies are incomplete. Thus
far, we have only the data presented by Father K. M. Matthew in
his highly acclaimed Flora of the Tamilnadu Carnatic (1984), where he
points out that, within his Flora area, the species is known only from
a single population of 20 trees. The only records we have seen for
other locations date from the last century and may well be based on
cultivated material. It is our hope that more populations, further
afield, will come to light and we urge Indian readers to bring to our
attention any of which they know. This species has been in
cultivation at the Botanical Gardens at Bogor and Calcutta.
Specimens at Bogor died before coming into flower. Trees obviously
© Bentham-Moxon Trust 1994. 9 1
grew well at Calcutta producing flowers and fruit over many years
but this was in the last century and it is not known if the species is still
represented in Calcutta Botanic Gardens.
Far to the west, the half-dozen species of Hildegardia native to
Africa and Madagascar all differ from their Asian sisters in that the
flowers have tubular perianths. The Asian species have much
smaller flowers, with perianths divided to the base into five reflexed
lobes, and they seem to flower when more or less leafy. Curiously, the
Cuban species, H. cubensis (Urb.) Kosterm., the sole representative
of the genus in the Americas, is intermediate in flower size and
lobing; its perianth is tubular, but divided to about half way.
Described by Ignatz Urban (1924), it was recorded as being
endangered only 30 years later (Alain & Lean, 1953), though
sightings have since been recorded. By now it may be extinct or
nearing extinction in the wild, though at least one specimen is known
from a botanic garden so there is a ray of hope for the longer term.
Returning to the Old World, the most flamboyant species are
undoubtedly those from Madagascar. Hildegardia erythrosiphon
(Baill.) Kosterm., though never described as common, is scattered
through a large area of the south and west of Madagascar s spiny
desert region famed for its bizarre and diverse community of
succulent plants. Some of these are much sought after and endan-
gered through over-collection for cultivation by enthusiasts as pot
plants (Knees, 1988), but they are also threatened by overgrazing
and habitat destruction.
Hildegardia ankaranensis (Arenes) Kosterm. is more restricted in
distribution. It grows only in the Ankarana region of the north west
of Madagascar amongst semi-deciduous forest, clothing an outcrop
of vertical, wafer-thin, knife-edged limestone rocks. When hit with
a stick, or a foot, such rocks produce a ringing sound, hence the
onomatopoeic Malagasy word 'Tsingy' for these rocky places.
Hildegardia ankaranensis is unusual in having slightly trilobed (rather
than cordate) leaves, and huge inflated (rather than flattened)
leathery fruits. The species was discovered as recently as 1956 and
only three flowering specimens are known.
The third and last species from Madagascar, H. perrieri (Hochr.)
Arenes, grows only in the wet rain-forest that still clothes patches of
the steep scarp on the island's eastern side. It has the largest flowers
by far: the leathery perianth-tubes are fully 5 cm long and 1.3 cm
wide. Only two localities were known until November 1989, when
92 ©Bmtham-MoxonTrustI994.
the Parisian botanists Thierry Deroin and Frederique Badre were on
a collecting expedition in the remote mountains near Marojejy. One
morning they were disturbed by heavy, trumpet-shaped pinkish
yellow-green flowers falling from the canopy on to their tent; they
had discovered a third locality more than a hundred kilometres
removed from those previously known.
Continental Africa holds the last three species of the genus. The
two East African species are widely separated. Hildegardia migeodii
(Exell) Kosterm. was discovered in 1929 by F. W. H. Migeod on a
fossil-hunting expedition at Tengaduru, in back-of-beyond
Tanzania. Fortunately, he was able to make a series of collections
over a year, representing every stage of growth, so we have a good
picture of the species. Unfortunately, the species has not been
collected from Tanzania in the intervening 60 years, though a
collection of what appears to be this species (we have only a
photograph) from confiict-ridden northern Mozambique was made
in 1948. Hildegardia migeodii is unusual in the genus in its furry seeds,
very long leaf-stalks and the unusual internal structure of its flowers.
Far to the north, in war-torn Somalia, H. gillettii Dorr &
L. G. Barnett was named after Kew'sjan Gillett only in 1990. Four
populations of the bottle-trunked trees have been discovered over
the last few decades but all from a single degree square. At two of
these sites there is but a single individual and nowhere are more than
eight trees known. Only one flowering specimen is known; all the
others are sterile and fruits have yet to be found (Mats Thulins,
pers. comm.).
In West Africa, the eleventh and final species, H. barter! (Mast.)
Kosterm., is completely atypical of this genus which appears to have
a death-wish, being not remotely threatened with extinction. It is
widespread through half a dozen countries from Guinea to Game-
roun. Though its natural habitat is the border of evergreen with
deciduous forest, there is evidence that suggests some planting by
man. Certainly the local people of West Africa have a plethora of
names and uses for the tree. The bark is widely used as a fibre for
ropes and was considered to have a commercial potential of £15—20
per ton In 1908 (about £400 in present-day terms). The bark is also
used as a sponge by the Hausa, whilst the seed is reported to be good
eating, tasting like a groundnut (Enti, 1968). The species is known to
grow well and rapidly on thin soils so potential for land reclamation
has been suggested (Enti, 1968). It has been cultivated in the Palm
© Bentham-Moxon Trust 1994. 93
House at Kew since at least 1965 and a specimen there today is 3 m
tall. Menninger (1962), aspecialistonflowering trees, states thatitis
underexploited as an ornamental; certainly all who refer to this
species comment on its spectacular flowers. If one species of
Hildegardia has so much to offer mankind, what a tragedy it would be
to lose the other ten. It seems of utmost urgency to establish these
species in cultivation to secure their future.
REFERENCES
Alain, H. & Leon, H. (1953). Flora de Cuba 3: 290. Habana, Cuba.
Cheek, M. & Leach, G. (1991). Hildegardia (Sterculiaceae) new to
Australia. Kew Bull. 46: 72.
Enti, A. A. (1968). Distribution and ecology ofHildegardia barter! (Mast.)
Kosterm. Bull. Inst. Fond. Afr. Noire, ser. A, 30: 881-895.
Knees, S. (1988). Plants in Peril, 12. Euphorbia francoisii Leandri
(Euphorbiaceae). Kew Mag. 5: 88-92.
Matthew, K. M. (1984). The Flora of the Tamilnadu Camatic 3(1): 145.
Tiruchipalli, India.
Menninger, E. A. (1962). Flowering Trees of the World for Tropics and Warm
Climates. Heathside Press, New York.
Urban, I. (1924). Symbolae Antillanae 9: 235. Borntraeger, Berlin.
BOOK REVIEWS
Scandinavian Ferns. Benjamin 011gard and Kirsten Tind. 317 pp., 114
colour plates, 103 line drawings. Rhodos International Science and Art
Publisher, Copenhagen. 1993. Hardback: ISBN 87-7245-532-2, Danish
kr. 425. Paperback: ISBN 87-7245-530-6, Danish kr. 375.
This book, written in English, is purported to be the first one dedicated to
Scandinavian Pteridophytes (ferns and fern allies) and covers those species
which have been recorded in Denmark, Norway and Sweden.
The text is written in a manner which can be easily understood by both
the amateur and professional botanist. The species and their characteristics
are given prominence in the work and are dealt with in systematic order
within 'the framework of the prevailing current classification'. The Checklist
of European Pteridophytes by Derrick, Jermy and Paul [published in
Sommerfeltia 6: 1-94 (1987)] is followed almost entirely. Of the 83 species,
subspecies and varieties, together with 25 of hybrid origin, which are found
in Scandinavia, 73 are described, giving details in most instances of their
reproduction, variation, distribution, ecology, uses, nomenclature and
synonymy. In botanical publications the etymology and synonymy are
usually placed immediately after the accepted names of the species but in
this work they appear towards the ends of the individual accounts.
Interesting and important facts are brought into the text, especially
under the family and genera headings, including distribution patterns
94 © Benthiim-Moxon Trust 1994.
