29 



SPECIES OP PRICKLY-PBAR. 



Historical. — There appears to be consider- 

 able confusion as to the number and actual names 

 of the species of Opuntia foiind naturalised in 

 South Africa. P. MacOwan, in 1888 (1897, p. 2), 

 referred to several — viz., 0. tuna, 0. vulgaris, 

 0. dillenii, and 0. aurantiaca; but mentions only 

 the first and third as actually occurring there. He 

 also stated (p. 5) that he had sent hundreds of 

 cuttings of 0. tuna to Angra Pequina, in German 

 South- West Africa, Schumann (1899 a, p. 30) 

 referred later to the fact that 0. tuna is wild in 

 Namaland,. but he associated the name with a 

 quite distinct type of Opuntia, 0. dillenii, Haw., 

 being regarded by him (1899, p. 724) as a 

 synonym of his 0. tuna. 



In July, 1891, A. C. Macdonald (1891), a, 

 p. 21; 1891 b; 1892 a, p. 22; 1897 a, p. 28) 

 referred all the South African Prickly-pears 

 to one species, 0. tuna, of which there exist two 

 varieties — the " thorny -leaved " form locally 

 called the Doornblad, and a much less spiny- 

 jointed pear called the Kaalblad. He included 

 also that form on which the Wild Cochineal 

 Insect occurs. This, we know, is a distinct 

 species — 0. monacantha. Next year Dr. Marloth 

 (1892 a, p. 11; 1892 b, p. 18) showed that 

 there were four species found naturalised — viz., 

 0. monacantha, 0. tuna (the two above-mentioned 

 varieties), a species resembling 0. dillenii, and 

 another, probably 0. pusilla. 



In 1892 (1897 b, p. 36) Macdonald referred 

 to the last-named as a possible dangerous pest. 



I. H. Burkill (1911, p. 290) has stated re- 

 cently that the Cape contains 0. monacantha, 0. 

 decumana, perhaps 0. triacantha, and possibly 

 0. elatior, or, if not, a very kindred species. The 

 first-named was collected by Oldenburg in 1772 

 (Burkill, I.e.). 



The observations and inquiries of the Com- 

 mission in South Africa point to the presence of 

 two species occurring commonly — viz., 0. m,ona- 

 cantha, found mainly along the coastal regions; 

 and 0. decumana,* the pest pear of South 

 Africa. Of the latter there are two forms, the 

 spiny and the comparatively spineless, these 

 having been formerly determined by Kew autho- 

 rities as 0. triacantha\ and 0. decumana, respec- 



* The name O. decumana is used in this section with » 

 considerable degree of doubt. The South African doorn- 

 blad and kaalblad belong to the same group of species as 

 0. ficua indica, O. decumana, and the " red and yellow 

 Mexican species " of our Rockhampton district. These, 

 together with many others, are Mexican white-spined 

 forms, a large number of which have not as yet been 

 satisfactorily defined, though Dr. Griffiths, of Washington 

 B.C., has done, and is doing, a great deal towards differ- 

 entiating the various species and varieties growing wild in 

 the Mexican highlands. The term O. decumana should 

 probably be restricted, as has been done in the preceding 

 section of this report, to certain almost or quite spineless 

 forms possessing very large segments — ^much larger and more 

 variable in shape than the kaalblad. It is often regarded as 

 being merely a variety of 0. ficus indica. The common 

 South African species or varieties, kaalblad and doornblad, 

 are, however, quite distinct from the 0. ficus indica of the 

 Mediterranean littoral. The name 0. decumana is retained 

 for conveniejice, as it expresses a nearer relationship to the 

 forms under consideration than does the name 0. tuna, 

 which is now applied by Dr. Britton to the common 

 Jamaican species which is allied to, and grows in company 

 with, 0. dillenii on that island. 



t The term O. triacantha is now restricted to a rather 

 low-growing, brittle species, native to certain of the West 

 Indian Islands. 



tively. In addition to these two species, there 

 is another, 0. aurantiaca, whose growth has 

 caused alarm in certain districts. 



Besides these three, certain others have been 

 met with, but they are comparatively rare. 



MacOwan's and Wallace's (1896, p. 88) 0. 

 tuna is the same as that called 0. decumana in 

 this Report. 0. vulgaris,* of the former, is pro- 

 bably only a variety of the same species. His 0. 

 dillenii and 0. aurantiaca we do not know; 0. 

 aurantiaca did not call for attention until much 

 later. The four species mentioned by Dr. Mar- 

 loth are quite distinct. That described by him as 

 resembling 0. dillenii in many ways, and said 

 to occur in a certain spot in Capetown, has now 

 been entirely destroyed and, therefore, as far as 

 known, does not exist naturalised in South Africa. 

 It is probably the same as that referred to as 0. 

 dillenii by MacOwan. Mr. Burkill's 0. elatior ( ?) 

 is evidently this species, photographs of which 

 were sent to Kew Herbarium by Dr. Marloth, 

 and were recently inspected by Mr. Burkill (fide 

 Mr. N. B. Brown, Assistant Keeper, Herbarium, 

 Kew). No trace of 0. elatior was found. Mac- 

 donald 's and Marloth 's 0. pusilla is 0. 

 aurantiaca. 



The prickly-pears occurring in South Africa 

 are thus: — 



0. monacantha, Haw. 

 0. decumana, Mill. 

 0. aurantiaca. 

 0. fulgidal 

 0. microdasys. 

 Opuntia lindheimeril 

 Opuntia spinulifera. 



In addition to these, there are others found 

 growing in gardens, while Nopalea cochinelifera 

 is being grown near Pretoria and at IMiddelburg, 

 Cape Province, as fodder for cattle and ostriches. 



Opuntia monacantha. — 0. monacantha 

 calls for slight mention, as it has already been 

 referred to in this report. In South Africa 

 it is commonly called the Sour Prickly-pear, 

 either from the fact that it grows on " sour"' 

 land or from the fact that its fruit remams 

 sour— both explanations having been published. 

 As already mentioned, it was for a time regarded 

 in South Africa as being merely a variety of the 

 spiny form of 0. decumana (Macdonald, 1891 

 a, b; Marloth, Roy. Soc. S. Afr., 1906, p. 15). 

 This species has evidently been naturalised in the 

 country for a long time, as Oldenburg had col- 

 lected it in 1772 {fide Burkill). 



Although 0. monacantha was seen to be 

 utilised occasionally for making hedges in 

 Pietersburg and Pretoria in the Transvaal, it 

 was mainly along the coastal regions of Cape 

 Colony and Natal that the plant was found wild. 

 It may be seen in more or less isolated patches 

 near Durban, Pietermaritzburg, and Avoca in 

 Natai; while in the Cape Province one may find 

 it scattered along the coast between Capetown 

 and Bast London. It does not apparently thrive 

 on the soils of the Karoo, these being compara- 

 tively rich in lime. It may be met mth at or 



*~o7mclqari8 may probably refer to 0. monacantha as 

 well, judging from the scant account of it ,r:ven by Mac- 

 donald (1891 a, p. 21). 



