Cactaceae, Opuntia spp., prickly pear, raiketa, de France (Mauritius) in view of planting the seaside of the fort and thus provide an impregnable barrier (Decary rakaita, raketa 1947). The cactus was imported in 1769 from either Réunion or Mauritius and by 1819 the plant was Pierre Binggeli observed to be protecting fields and gardens from animals and thieves in the south of the island. In 1865 A. (2003) In Goodman S.M. and J.P. Benstead (Eds) The Grandidier walked about 40 km inland near Cap natural history of Madagascar, pp. 335-339. University Sainte-Marie along a track lined with prickly pears of Chicago Press, Chicago. (François 1938). Although the plant was first introduced into the relatively humid conditions of Antanosy, it was American cactus species of the genus Opuntia have been rapidly dispersed by native people and managed to widely introduced around the world chiefly as a source of spread rapidly into the sub-desertic region of Androy food for herbivores and humans as well as a hedge plant during the latter part of the 18th century (Decary 1947). (Russell & Felker 1987; Le Houérou 1996). A number of species have subsequently become invasive in many arid The area south of the line Tsiombe-Montovositra- regions including one species in the southwest of Beloha-Ampotaka was indicated on an early 20th-century Madagascar. The case of Opuntia monacantha Haw. map as the 'region cactée' where the vegetation was (Cactaceae) in Madagascar has been largely forgotten but dominated by the prickly pear. It is also roughly the it is a perfect example illustrating the appearance, boundary between the calcareous and crystalline rock dominance, and eventual disappearance of an invasive formations. In the latter zone the cactus was present but plant. Because the plant had been widely used by some did not appear to spread much and constituted up to 10- native ethnic groups and their livestock, but had also 20% of the vegetation cover. Elsewhere in the south it wasted much agricultural land and seriously hindered represented 40-50% of the vegetation. The densest cactus people's mobility, its disappearance from the island's formations (up to 100% cover), where all native bushy southern landscape, caused by the introduction of a scale plant species had vanished, were reported around insect (Dactylopius), generated much controversy. Nifondo and Ambalanosy to the south of Beloha (Decary 1921, 1930a; the 1921 paper refers to his unpublished The taxonomic nature of the invasive Opuntia in Opuntia distribution map). Madagascar was for a long time unclear and the species was variously called O. monacantha, O. vulgaris, and O. In the Toliara region the species was only found on dillenii. According to Chevalier (1947) the invasive alluvial soils along the Fiherenana River and on the species was O. monacantha (often called O. vulgaris coastal dunes as it was not mentioned by Poisson (1921) Miller in the literature) whilst O. dillenii did not appear in his description of the inland vegetation made during to have been introduced to Madagascar. Due to the lack his trip to Betioky. Thus, in the southwest prickly pear of collected material, Aymonin (1983) could not properly favored areas of low rainfall, sandy and alluvial soils, assess the status of the genus, but he also listed O. and soils overlaying calcareous rock formations. cochenillifera as cultivated and suspected that other Although it had become a 'pest', dominating many of the species had probably been introduced to Madagascar. It modified vegetation types of the region, Perrier de la is now recognized that the name O. vulgaris should refer Bâthie (1932) noted that the species was poorly adapted to a different, North American, species and the correct to the climate of the Toliara region. Its fruits hardly ever name is O. monacantha, although it must be noted that ripened and generally ended up changing into cladodes, no neotype has been designated (Leuenberger 1993). O. whereas in the slightly wetter Androy it produced large monacantha is a succulent shrub up to 5 to 6 m high quantities of fruit. which green branches consist in flattened stem units (cladodes). It bears large (7-9 cm in diameter) yellow Elsewhere in Madagascar Opuntia monacantha used to flowers, and the 7 cm long pear-shaped fleshy fruit, a be common around villages on the western side of the berry, is red containing many seeds. The plant is covered central highlands, between 1500-1800, but its spread was with sharp, 3-4 cm long. Undefined varieties, especially limited and it did not form vast impenetrable stands. In spineless, of O. ficus-indica, a morphologically similar the humid eastern regions and in the warmer zone of the species, were introduced during the early part of the northwest and west, Opuntia only grew with difficulty 20th-century. and eventually disappeared (François 1930).

The arid southwestern region of Madagascar was During the 18th-century the French re-established inhabited by two pastoral ethnic groups, the Antandroy military positions along the east coast of Madagascar, and Mahafaly, each consisting of many clans, which had including one at Fort-Dauphin (Tolagnaro). Various forts been pushed to this inhospitable part of the island by had been built since 1643 but were often attacked and more powerful tribes. Especially in the case of the destroyed (Deschamps 1972). On 12 December 1768 Antandroy, the chief purpose of life was to amass as Governor Moldave wrote in his diary that a request had many zebu cattle as possible. During funerals most of the been made for the supply of Opuntia cladodes from Ile deceased's animals were slaughtered and eaten and in

Binggeli, P. (2003) In Goodman S.M. and J.P. Benstead (Eds) The natural history of Madagascar, pp. 335-339. 6 effect these cattle provided a relatively small proportion suggested that it could be planted to protect forest edges of the Antandroy's diet. The zebus were a sign of wealth, from fires. essential to obtain a bride for instance, and were readily stolen. To these people the spread of the dense Opuntia In view of the drawbacks of Opuntia monacantha (e.g. stands appeared to be highly beneficial providing hiding spines, invasiveness, and health hazards) a thornless places from enemies for themselves and for their cattle. replacement was sought. Such a plant, then commonly In areas where agriculture was practiced it provided a called O. inermis (probably cultivars of O. ficus-indica), living fence against roaming cattle. During the early existed around Antananarivo around 1900 and by 1903 decades of colonial rule these stands also allowed the the military had it planted in the close vicinity of its indigenous people to escape conquest for a few years and Androy's fortified posts as a feed for their oxen (Decary then hide from the French authorities and the tax 1921 reported that in the Androy the plants exhibited authorities in particular. During dry months and short hard spines). Since 1912 Perrier de la Bâthie (1928) especially during periods of drought the cacti provided had promoted the establishment of spineless forms of food and water for cattle and humans. Three varieties of prickly pears and was in favor of the eradication of O. fruits were recognized and during the dry seasons were monacantha. He argued that in so doing the benefits of often the only foods on sale at local markets. The the invasive cacti would remain whereas its serious Antandroy considered the fruit of O. monacantha drawbacks would be eliminated. In 1919 an administrator superior to that of the thornless cultivars (Decary 1928, prescribed the planting of 1 ha plots throughout the 1930b, 1933; François 1930; Perrier de la Bâthie 1934). region. Most of the military plantations were abandoned but in the 1920s relics were known to exist in a few The main means of dispersal of Opuntia was by human locations whereas the fate of the 1 ha plots was unknown agency. New fields were established in scattered (Perrier de la Bâthie 1928). vegetation and delimited with cactus cladodes laid on the ground 5-6 m apart (Decary 1930a). Once abandoned the Due to the taxonomic difficulties in identifying species of cactus would rapidly overrun a field, as every part of the the scale insect genus Dactylopius, much confusion has plant broken off, including fruits, could root and form a occurred as to the nature of the form introduced to new plant. At the end of the rainy season the plant, Madagascar, as indeed elsewhere in the world. Species of gorged with water, would become brittle and break in genus Dactylopius feed on specific taxa of Opuntia. windy conditions (Decary 1921). New foci of invasion Some of Dactylopius have had much economic were also initiated via seeds dispersed by cattle (Decary importance as they provided the cochineal crimson dye 1925a). Bird dispersal (Corvus spp.) has been reported in whilst others have been used in some of the first highly South Africa (Dean & Milton 2000) and was probably an successful biological control programs. What happened agent of spread in Madagascar too. in Madagascar appears to be a continuation of the haphazard and confused efforts to use introduced The spiny and impenetrable nature of Opuntia thickets Dactylopius species for biological control or for dye had a number of serious drawbacks but these were production in many parts of the tropics and subtropics somewhat different in nature to indigenous and colonial where Opuntia spp. had become major weeds. In people. To both groups the wind-blown fruits' hairs southern India and Sri Lanka, according to Beeson caused lung problems and conjunctivitis. Both thorns and (1934), O. monacantha was almost destroyed by the D. hairs induced intestinal inflammations in cattle often indicus, probably mistaken for D. coccus, which was resulting in death (Petit 1929a). The predilection of the introduced in order to produce natural dye. The insect cactus for more fertile soils found along rivers meant that was then introduced to the Natal Province of South agriculture was no longer possible as the dense stands Africa and in 1913, at the request of Mr d'Emmerez de were too expensive to clear. The infestations also became Charmoy, it was sent to Mauritius. It proved to be refugia for a number of mammal species, Rattus in ineffective there against O. monacantha, but had an particular (Perrier de la Bâthie 1928; Petit 1929a). impact against O. tuna, however a second batch of these insects, obtained from South Africa as well, prospered The impact on native flora and fauna was not reported and O. monacantha was destroyed on Mauritius (Petit although Opuntia became the dominant feature of much 1929b; B.G. 1936). Although Frappa (1932) described of the southern landscape. The extent of the spread of this and identified all the Malagasy central highland cactus into undisturbed vegetation is a matter of specimens he collected as D. tomentosus Lam. and conjecture. In view of Grandidier's conviction that the suspected that the insect in the southwest was the same vegetation near Cap Sainte Marie was of little botanical species, the exact taxonomic status of the species present interest, based on his field observations made during his in Madagascar requires confirmation. trek inland, it is clear that the prickly pear had smothered much of this unique vegetation. An appreciation of this In 1921 R. Decary, a French Administrator and keen region’s plant diversity arose only after the cactus's naturalist, suggested that the cochineal D. tomentosus demise (François 1938). Humbert (1927) identified one should be introduced to the south of Madagascar in order positive effect, that Opuntia was used as fire breaks and to establish a commercial dye industry (Decary 1921, p. 66). In 1924 H. Perrier de la Bâthie, a leading Malagasy

Binggeli, P. (2003) In Goodman S.M. and J.P. Benstead (Eds) The natural history of Madagascar, pp. 335-339. 6 naturalist and 'consultant' to the colonial administration, prevented by the prickly pear, in deforestation increased published a short note stating that in 1923 an unknown markedly and Decary (1933) viewed this threat with individual that he suspected to be a colonist had much concern. introduced ‘Coccus cacti’ from Réunion or Mauritius to Antananarivo. Unpublished correspondence recently Although the disappearance of the cactus, a prickly discovered by Middleton (1999) showed that Perrier de la nuisance, was considered as highly beneficial by every Bâthie accused Decary of actually requesting the one in the central highlands, its imminent disappearance consignment of cochineal insects (which the latter from the southwest ignited a major controversy as to the denied). The reasons and the individual(s) responsible for importance of the cactus to the sustainability of the the introduction of the scale insect remains open to environment and the maintenance of the indigenous debate, but within a short period of time the insect totally populations in the region. Decary (1925b, 1928) asserted devastated the Opuntia population on the western side of that without the prickly pear part of the country would be the Andrefandrova Hill as well as all the plants around uninhabitable and its loss as a food and water resource Antananarivo. The insect propagated itself easily as the would inevitably lead to famine. In contrast, Perrier de la larvae were either dispersed by wind or by human Bâthie (1928, 1934) thought that the cactus did indeed movement of infested plant material (Perrier de la Bâthie help in alleviating famine and thirst but its presence or 1928; Petit 1929b; B.G. 1936). However, as the insect is absence did not cause famine. Indeed he pointed out that monophagous it did not affect the thornless forms (B.G. in 1903 famine was extensive despite the presence of 1936). Opuntia. Petit (1929a) claimed that the importance of prickly pear as a food source during famine had been In November 1924 individuals of Dactylopius were sent exaggerated and despite its disappearance no famine had to Toliara (Perrier de la Bâthie 1928) where, according to to be feared. Yet, when the next drought afflicted the Petit (1929b), colonial farmers and native people region in 1930, it had a major impact on the local facilitated its spread. According to Middleton (1999), populations. Perrier de la Bâthie was responsible for the introduction of the cochineal beetle to Toliara. She did not believe A detailed, but partial, socio-political analysis of the natives propagated the insect as reported by Petit and events surrounding the introduction of the cochineal and even wondered whether Petit deliberately spread the especially the views of and interactions between the two agent during the field investigations he was carrying out main protagonists, Decary and Perrier de la Bâthie, has in the region at the time. The cochineal progressed at a recently been published by Middleton (1999). This rate of about 100 km per year (Frappa 1932, who review, however, failed to take into account statements provides a rather fanciful map) and within four years O. contrary to the thesis of the 'champion of Malagasy monacantha was variously described as wiped out or cactus' (Decary) versus the 'peripheral amateur' (Perrier eradicated from the south of the island (e.g., Koechlin et de la Bâthie) and his ally Petit, an entomologist, as well al. 1974). as to properly report the reassessment made by Decary in 1932 (Decary 1933). A detailed analysis of the debate is During that period it was reported that male cochineal beyond the scope of this review and will not be dealt constituted, at certain times of the day, huge swarms with here. which were disagreeable to travelers (Decary 1928). Jolly (1980) reported an old French lady as saying that The impact of the near eradication of Opuntia is unclear "swarming clouds of cochineal would hit the car and the and no firm conclusions as to extent of the buffering windscreen and be crushed - the automobile seemed afforded by the cactus during severe droughts. drenched in blood". In the Androy areas where the cactus Undoubtedly the absence of Opuntia caused severe had been destroyed it was nearly impossible to obtain a hardship during the 1930 drought and resulted in the cochineal specimen. By June 1929 François (1930) death or migration of many people. Although it has been observed thousands of hectares of dead trunks with the stated that many cattle died just after the disappearance ground covered with a thick spiny 'compost' and noted of the cactus and during the drought, on the basis of the that the native bush, suddenly released from competition, figures given by Decary (1933) the number of cattle had taken full advantage from this fertilizer and the decreased by 20% during the period of the 1930 drought. extreme south of Madagascar had gained a new However, between the censuses of 1922 and 1923, when physiognomy. In late 1932 Decary (1933) reported that in there was plenty of cactus around and apparently no many places the ground was still covered by heaps of drought, cattle numbers dropped by 31%. No clues can brittle spines. He noted that much of the landscape was be traced to explain such dramatic variation in cattle not only much more open, in places with scarcely a bush populations. Following the 1943 drought Bérard (1951) in sight, but that the dominant color of the vegetation, reported that the Antandroy believed that cattle would especially during the dry season, was grayish instead of have been saved and villages not depopulated had the green. The columns of smoke produced during the cactus been present and Bérard considered that the preparation of prickly pear for cattle, which had been a effects on cattle would have been mitigated. Besides the feature of the region during the dry season, were now short comment by Perrier de la Bâthie (1934) and absent. On the other hand the use of fire, formerly Decary's statements that for several weeks the Anjeka

Binggeli, P. (2003) In Goodman S.M. and J.P. Benstead (Eds) The natural history of Madagascar, pp. 335-339. 6 Clan of the Antandroy drank water extracted from the and a decade earlier Appert et al. (1969) noted that the cactus and much cattle were slaughtered (Decary 1930a), "scale insect still exists, but finding it and discovering its information on the impact of the previous droughts (e.g. breeding centres is difficult." The importance of prickly 1903, 1913) is entirely lacking. pear in the landscape is supported by Nicoll & Langrand (1989) who noted that fruits and 'leaves' constituted a After the disappearance of Opuntia monacantha around seasonally important source of food for people and cattle ten taxa of American of Opuntia cactus were introduced in the Réserve Spéciale de Cape St Marie. Three types of in 1925 to an Ambovombe farm (Decary 1947). The fate opuntias can now be be found in southern Madagascar of these plants is unknown but Decary (1933) stated that (M. Pidgeon personal communication). One bears long in 1930 two nurseries were established and by 1932 had spines (7-9 cm) which is very rare but the Antandroy produced 80,000 plants. It was then envisaged that within claim that it used to be more common and has been three to four years one million cladodes would be replaced by ‘spineless’ and small-sized spined varieties distributed to all villages so that a new food reserve (presumably the first type refers to O. monacantha and would be constituted. This program was probably not the latter two to varieties of O. ficus-indica). Opuntia sp. implemented as Bérard (1951) stated that the promotion is once again present in the vicinity of Toliara (R. and establishment of the plant in the countryside would Trevelyan personal communication). be the most useful task to be carried out. This Opuntia story in Madagascar underlines the After World War II and the famine of 1943 the Colonial complexities associated with invasive plants and their Government asked H. Humbert to reassess the impact of impacts on human societies (see Binggeli 2001 for the biocontrol agent and its consequences. Although further examples). In particular the understanding, Opuntia disappearance resulted in famine during the perceptions, needs, and aspirations of differing social and subsequent drought he viewed that, on balance, the cultural groups are markedly affected by variations in impacts were broadly beneficial especially because the geographical location, climate, vegetation and history. It thornless form had been multiplied and disseminated also highlights the ability of humans to rapidly adapt to (Humbert 1947, 1949, 1953). He concluded that changes in plant resources. indigenous people were extremely satisfied by the substitution as fruits were sweeter (Bérard (1951) Prior to the Opuntia monacantha introduction and reported that in one day 2000 locals had eaten about a invasion, people colonized the southwest of Madagascar kilogram of fruit each at the Ambovombe Station) and as and live successfully in this arid region. They then a cattle food it did not have the drawback of the spiny obtained a new resource and adapted to an altered Opuntia. Other scientists have had very different views, environment dominated by the cactus. The Antandroy for instance, three entomologists specialized in biological often used to describe their relationship with the plant by control of insects asserted that the cactus "formed the the proverb 'Longo Tandroy sy Raiketa' - 'The Antandroy main element in the useful vegetation in South and the prickly pear are relatives' (Decary 1930a). Then, Madagascar" and that the introduction of the cochineal despite this close relationship (viewed by Jolly (1980) as was "the work of people who, thinking that they are illustrating “the interdependence of man and nature”), sufficiently informed and acting with commendable Decary (1933) reported that after the disappearance of intentions, play the role of the sorcerer's apprentice and the cactus the Antandroy had rapidly replaced it with set off an irreversible process with disastrous Agave ixtli. This American plant was used in a similar consequences" (Appert et al. 1969). They also considered fashion to delimit and protect fields and feed cattle. that, unfortunately, suitable conditions did not exist to However, it fulfilled these tasks less effectively and did introduce enemies of the scale insect. Greathead (1971) not provide fruits for human consumption but yielded in his review of Malagasy biological programs noted that fiber instead. in the literature “the results [of the cactus destruction] are not regarded as beneficial”. Appert, J., Betbeder-Matibet, M., and Ranaivosoa, H. 1969. Vingt années de lutte biologique à Madagascar - Twenty years In recent years little appears to have been written about of biological control in Madagascar. L'Agronomie Tropicale 24: Opuntia in Madagascar but according to Rauh (1995, 555-585. 1998) it would appear that "some parts of the southwest Aymonin, G. 1983. Flore de Madagascar et des Comores: 145 even resemble some Mexican landscapes" once again and Cactées. Paris: Muséum National d'Histoire Naturelle. the cactus had "destroyed portions of the natural vegetation". He stated that O. monacantha "is often B.G. (after Silvestri, F.) 1936. Procédés biologiques employés planted as an impenetrable hedge around fields and pour combattre l'envahissement de certaines plantes nuisibles houses. Vast parts of southern Madagascar, the regions of aux cultures tropicales. Revue de Botanique Appliquée et Ambovombe, Amboasary, Tsihombe, Tanjona Vohimena d'Agriculture Tropicale 16: 649-652. (Cap Sainte Marie), are covered with dense thickets of Opuntia" and the reason for this recovery and renewed Beeson, F. C. 1934. La raquette épineuse et les cochenilles. Revue de Botanique Appliquée et d'Agriculture Tropicale 14: spread being the disappearance of the cochineal. Yet a 358-360. photo in Jolly (1980) clearly showed an infected plant

Binggeli, P. (2003) In Goodman S.M. and J.P. Benstead (Eds) The natural history of Madagascar, pp. 335-339. 6 Bérard, H. 1951. Le problème agricole du ravitaillement des Greathead, D. J. 1971. A review of biological control in the populations dans l'extrême sud de Madagascar, deuxième Ethiopian region. Technical Communication Commonwealth partie. L'Agronomie Tropicale 6(5-6): 265-286. Institute of Biological Control 5: 1-162. Binggeli, P. 2001. The human dimensions of invasive woody plants. In The great reshuffling - Human dimensions of invasive Humbert, H. 1927. La destruction d'une flore insulaire par le alien species, ed. J. McNeilly, pp. 145-159. Gland: IUCN. feu; principaux aspects de la végétation à Madagascar. Mémoire

de l'Académie Malgache 5: 1-80. Chevalier, A. 1947. Dossier sur les cactus (Opuntias) espèces fruitières et fourragères. Espèces nuisibles. Revue Humbert, H. 1947. Changements survenus dans la végétation Internationale de Botanique Appliquée et d'Agriculture du Sud de Madagascar. Revue Internationale de Botanique Tropicale 27: 444-454. Appliquée et d'Agriculture Tropicale 27: 440-444. Coursin, L. 1934. Le réseau routier à Madagascar. La Revue de Humbert, H. 1949. Rapport de mission botanique … Madagascar 6: 27-61. Madagascar (1946-1947). Le Naturaliste Malgache 1: 61-79. Dean, W. R. J., and Milton, S. J. 2000. Directed dispersal of Humbert, H. 1953. Un example suggestif de désertification Opuntia species in the Karoo, South Africa: are crows the provoquée: les territoires du sud de Madagascar. Le Naturaliste responsible agents? Journal of Arid Environments 45: 305-314. Malgache 5: 5-17. Decary, R. 1921. Monographie du district de Tsihombe. Jolly, A. 1980. World like our own - Man and nature in Bulletin Economique de Madagascar - Colonie de Madagascar Madagascar. New Haven: Yale University Press. et Dépendances 18(1): 5-38; 18(2): 41-75. Koechlin, J., Guillaumet, J.-L., and Morat, P. 1974. Flore et Decary, R. 1925a. La dissémination des graines chez quelques végétation de Madagascar. Vaduz: Cramer. plantes de Madagascar. La Feuille des Naturalistes 46: 134-136. Le Houérou, H. N. 1996. The role of cacti (Opuntia spp.) in erosion control, land reclamation, rehabilitation and agricultural Decary, R. 1925b. L'utilisations des Opuntias en Androy. Revue development in the Mediterranean basin. Journal of Arid de Botanique Appliquée et d'Agriculture Coloniale 5: 769-771. Environments 33: 135-159. Decary, R. 1928. A propos de l'Opuntia épineux de Madagascar. Leuenberger, B. E. 1993. Interpretation and typification of Revue de Botanique Appliquée et d'Agriculture Coloniale 8: Cactus opuntia L., Opuntia vulgaris Mill., and O. humifusa 43-46. (Rafin) Rafin (Cactaceae). Taxon 42: 419-429. Decary, R. 1930a. L'Androy (Extrême Sud de Madagascar): Middleton, K. 1999. Who killed 'Malagasy cactus'? Science, Essai de monographie régionale. 1. Géographie physique et environment and colonialism in southern Madagascar humaine. Paris: Société d'Editions Géographiques, Maritimes et (1924-1930). Journal of Southern African Studies 25: 215-248. Coloniales. Nicoll, M. E., and Langrand, O. 1989. Madagascar: revue de la Decary, R. 1930b. La destruction des cactus par une cochenille conservation et des aires protégées. Gland: WWF. à Madagascar: ses conséquences économiques et sociales. Annales de la Société Linnéenne de Lyon 75: 101-117. Perrier de la Bâthie, H. 1924. Introduction à Tananarive du «Coccus cacti» ou cochenille du Figuier d'Inde. Bulletin Decary, R. 1933. L'Androy (Extrême Sud de Madagascar): Economique de Madagascar - Colonie de Madagascar et Essai de monographie régionale. 2. Histoire. Civilisation. Dépendances 21: 222. Colonisation. Paris: Société d'Editions Géographiques, Maritimes et Coloniales. Perrier de la Bâthie, H. 1928. Les pestes végétales à Madagascar. Revue de Botanique Appliquée et d'Agriculture Decary, R. 1947. Epoque d'introduction des Opuntias Coloniale 8: 36-42. monocantha dans le Sud de Madagascar. Revue Internationale de Botanique Appliquée et d'Agriculture Tropicale 27: 455-457. Perrier de la Bâthie, H. 1932. Les plantes introduites à Madagascar. 5. Espèces introduites ne faisant pas partie des Deschamps, H. 1972. Histoire de Madagascar. Paris: Editions catégories précédentes. Revue de Botanique Appliquée et Berger-Levrault. d'Agriculture Tropicale 12: 296-301. François, E. 1930. De l'emploi de l'Herbe Kikuyu à Perrier de la Bâthie, H. 1934. Les famines du Sud-Ouest de Madagascar. Revue de Botanique Appliquée et d'Agriculture Madagascar - Causes et remèdes. Revue de Botanique Tropicale 10: 287-289. Appliquée et d'Agriculture Tropicale 14: 173-186. François, E. 1938. Alfred Grandidier - botaniste. La Revue de Petit, G. 1929a. Sur l'introduction à Madagascar du Madagascar 22: 27-48. «Dactylopius coccus Costa» parasite de l'«Opuntia vulgaris Mill.» Comptes Rendus des Séances de l’Académie Agricole de Frappa, C. 1932. Sur Dactylopius tomentosus Lam. et son France 15: 410-417. acclimatement à Madagascar. Revue de Pathologie Végétale et d’Entomologie Agricole de France 19: 48-55.

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Binggeli, P. (2003) In Goodman S.M. and J.P. Benstead (Eds) The natural history of Madagascar, pp. 335-339. 6