Director, Dr. Lewton Brain, who was formerly 

 Pathologist to the West Indian Department of 

 Agriculture, and whose sp^ial investigations of 

 plant diseases in that locality, it was hoped, 

 might have been extended to those of the Opun- 

 tias growing there. In a letter he referred to 

 Dr. Watts, the Imperial Commissioner for Agri- 

 culture at Barbados, as one who would no doubt 

 be able to render assistance to the Commission 

 in its inquiry. 



PENANG. 



The small collection of Cactacese in the 

 Penang Botanic Gardens was inspected, but here, 

 as at Java and Singapore, the hot moist climate 

 had a detrimental effect on all but a few species. 

 An unidentified white superficial fungoid growth 

 appeared to be able to attack and injure Cactaceee 

 under these climatic conditions. 



CEYLON. 



Visits were paid to the Royal Botanical 

 Gardens at Peradeniya, where assistance was 

 obtained from Mr. R. N. Lyne, the Director of 

 Agriculture, Mr. E. E. Green, the Government 

 Entomologist, and Mr. T. Petch, the Mycologist. 



The lastnamed investigator informed us that 

 Prickly-pear was very prevalent in the Northern 

 Province of the island and was found to some 

 extent in the dry zone along the south-eastern 

 coast from Tangalla to Hambantota. He was 

 not aware of the occurrence in Ceylon of any 

 fungoid or bacterial disease of Opuntias, such as 

 might be utilised in destroying them. 



Mr. Green, who is an authority on Coccidos 

 and who has recently published a paper on the 

 cultivated and wild forms of cochineal insects 

 (1912), gave us an opportunity to examine 

 mounted specimens of the species Coccus indicus, 

 Green, naturalised in India and Ceylon, as well 

 as of C. confusus capensis, which is now found 

 in South Africa. Living examples of the latter 

 were seen growing in his garden on Nopalea 

 cochinelifera, and were generously placed at the 

 disposal of the Commission for transmission to 

 Queensland. He believed that C. indicus was 

 now a rare insect since he had found it only 

 on a few isolated plants at Hambantota and 

 Tangalla (1912, p. 85). Its destructive work had 

 already been referred to in his paper, where the 

 host plant is quoted as 0. dillenii since that was 

 the only species of Opuntia recorded from the 

 island. He was not aware of any other insect 

 enemies of Prickly-pear in Ceylon. 



From information already available (Lewis, 

 1895, p. 279) it was known that Mr. P. A. Dyke, 

 formerly Government Agent for the Northern 

 Province, had in 1865, as well as previously, 

 introduced a cochineal insect from Jaffna, at the 

 extreme north of the island, and from Trincomalee 

 on the eastern coast, to MuUaittivu, where Prickly- 

 pear referred to as 0. dillenii was very common.* 

 The destruction of Opuntia caused by these 

 parasites was said to be so considerable that it 

 was a difficult matter to find a plant three years 

 later. Insects sent from Jaffna had also brought 

 about great havoc near Mattalau and Chinnaru, 



* The Tamil term naka kalli, with variations, is 

 applied indifferently at the present day to 0. dillenii and 

 0. monacantha. The same remark is true for the Sinhalese 

 name patuk or katu patuk (thorny patuk). 



while those which destroyed the Prickly-pear iii 

 the Vanni district (Chemmalai) had come from 

 Trincomalee by way of Nuwarakkalawiya. Prom 

 a reference to Dyke's Diary, 1865-68, given by 

 Lewis, it would seem that this coccus, which 

 appears to have been the wild cochineal, was 

 derived from Madras. 



The destruction just referred to was wit- 

 nessed by Sir William Twynam, K.C.M.G., who 

 was then Assistant Agent at Manaar under Mr. 

 Dyke (vid. Tryon, 1910, p. 188; 1911, p. 11). 



Mr. Thos. Steele,* while acting as Govern- 

 ment Agent in the Hambantota district (1872), 

 recorded the presence of this insect there as well 

 as elsewhere in the island, as a very destructive 

 enemy of Prickly-pear. On comparing it with 

 specimens of the true cochineal from Mexico, he 

 recognised that the Ceylon coccid was distinct 

 from it, though perhaps allied. 



After making the necessary preliminary 

 inquiries, it was decided to visit the northern 

 province where the insect had in 1865-8 proved 

 itself an exterminator; and also the district 

 which included Hambantota and Tangalla, where 

 more recent destruction was known to have been 

 occasioned. 



Visit to the Northern Peovincb. 



From Pallai, 222 miles from Colombo along 

 the Northern Railway, to Kankesanturai, 34 miles 

 further on. Prickly-pear was found to grow 

 sporadically, but in some places quite thickly; 

 and from the latter place westward to Kayts 

 Island and eastward to Point Pedro the same 

 noxious weed was found to be quite prevalent, 

 causing in some quarters much concern. The 

 area embraced by these limits affords the home 

 of an agricultural Tamil community, which in 

 some localities was already taking steps to 

 extirpate it. Prickly-pear was also found to 

 grow in large patches adjacent to the tobacco 

 fields on the island of Mandativu, and near the 

 town of Jaffna. Moreover, testimony received 

 suggested that it had a much wider distribution 

 in the Northern Province than even this personal 

 investigation disclosed. 



It was found that the pear was almost 

 exclusively Opuntia dillenii, Haw., which is the 

 only species of Prickly-pear recorded as being 

 naturalised in Ceylon, t 



Though 0. dillenii had been referred to as 

 the host of the Wild Cochineal insect in Ceylon, 

 first by Lewis (1895, p. 279) and lately by 

 Green (1912, p. 85), yet Burkill (1911) has 

 stated that the coccid which is found in India 

 and which Mr. Green has identified as also being 

 Coccus indicus, has been met with by him 

 exclusively on another species, 0. monacantha, 

 which is not recorded as a naturalised plant in 

 Ceylon. A careful search was made and though 



* Steele, Thos., Assist. Govt. Agent, in " Annual 

 Report on the Hambantota district, 1872," Administration 

 Reports, Ceylon, 1872, Colombo, by authority, 1873— 

 p. 165. 



t H. Trimen (" Handbook of the Flora of Ceylon, 

 II , p. 267) states that O. dillenii is the common cactus 

 found on waste ground and roadsides in the low country. 

 It occurs rarely in the moist regions, but is abundant m the 

 drier coastal districts. In parts of the Northern Province 

 it is a nuisance. It is called Katu-patuk by the Smhalese 

 and Naka-kalli by the TamUs. He mentions that the 

 species is an old introduction from South America. He 

 goes on to state that no other naturalised species occurs 

 in Ceylon. 



