Vol.. IX. No. 203. 



THE AGRICULTURAL NEWS. 



n 



The Cay- cay of Annam. 



An account of the cay-cay of Annam (Irringia 

 Olicfri) is contained in a report of the Director of 

 Agriculture, Forests and Commerce on the work of the 

 experiment stations and botanic gardens of Iiido-China 

 for the year 1908. It states that investigations under- 

 taken at the Agricultural and Industrial Laboratory of 

 Saigon have shown that the kernels of the seeds of 

 JrviiKjia Oliveri contain about .50 per cent, of a fatty 

 matter which is edible and capable of replacing the oil 

 obtained from copra in all its uses. 



It appears, however, from several enquiries that 

 this plant is not suitable for artificial planting, as infor- 

 mation furnished by the Forestry Service of Cochin- 

 China shows that the average crop produced by an 

 adult tree only amounts to about 2201h. (if fruit which 

 ■contains about 4-5 lb. of seeds. The latter only contain 

 about 18 to 20 per cent, of their weight of kernels, and 

 the weight of useful matter is thus not more than 9ft. 

 per tree. 



On a basis of an extraction of 50 per cent., one 

 tree could thus only furnish about 4i tb. of fatty 

 matter. The cultivation of this plant, under these 

 conditions, is not recommended, especially as its growth 

 is slow, and it does not produce useful crops before the 

 age of ten years. Another consideration is that, owing 

 to the great ramification of the principal branches, no 

 more than forty trees can be planted on each acre. 



Euphorbia Latex for Preventing (Jorrosion. 



In Newman's Metallic Structures an account is 

 given of the use of the milky juice of the Euphorbias 

 {spurges) for preventing corrosion. It is stated that it 

 is only in comparatively recent years that the preserv- 

 ing qualities of Euphorbia latex have been made use 

 of in engineering structures, and then only occasion- 

 ally. A description is further given of the way in 

 which this property was discovered. It appears that, 

 during a surveying expedition in Natal, it was noticed 

 that, when Euphorbia plants were cut by the clearing 

 knives, the juice formed a layer on them which could 

 only be removed with great difficult}'. Further experi- 

 ments with pieces of iron that had come into contact 

 with the juice showed that these did not rust, and that 

 when they were immersed in sea water, at Durban, 

 they remained free from barnacles and were not affect- 

 ed by any form of marine life. In Natal, laths coated 

 with Euphorbia latex, together with those which had 

 not been so treated, were thrust into nests of the white 

 ant {Termes hellicosus)\ after twenty-four hours, the 

 treated laths were found to be unaffected, while those 

 which had not come into contact with the juice were 

 completely riddled by the insect. It is further stated 

 that timber coated with Euphorbia latex remained 

 untouched by the sea worm. Teredo navalis, and 

 mention is made of the emploj'ment of the juice in 

 making paint. 



Since this, according to the Ai/rieulturalJournal 

 of the Cape of Good Ho2V>, as a result of enquiries on 

 the part of the Somerset East Chamber of Commerce, 

 it has been ascertained that the above statements 

 jegarding the preserving properties of the juice are 



correct, and that, although owing to its gummy nature 

 it is no longer used in paints, it is employed by makers 

 of compositions for ships' bottoms, and an attempt is 

 being made to create an export trade in the article 

 from Cape Colon3^ 



Change of Habits by Birds. 



Interesting notes on this subject appear in the 

 Proeei'ifings (f the Aijrirultn.ral Society of Triniilad 

 anil Tobago for November 1909. It has long been 

 observed that the habits of birds living in islands 

 differ materially from those of birds from the same 

 species which live on continents, and these differences 

 are specially noticeable among insect-eating birds. An 

 example is the carpenter bird, which is one of the 

 woodpeckers, and therefore essentially an insect feeder; 

 this has a close relative, the 'sap sucker', which feeds 

 on the sap exuding from holes made by it in the trunks 

 of trees. This habit of feeding seems to have been 

 comparatively recently acquired, for one species, the 

 )-ellowbellied sap sucker {Sphyropicas varius) is 

 known to capture and devour such insects as may come 

 within its reach. 



The ditfercncc? shown are probably due to the 

 fact that the supplies of food are more likely to suffer 

 a temporary interruption on islands than on conti- 

 nents, because the insect fauna of islands is 

 generally comparatively poor, and because much more 

 serious damage may be effected in islands by high 

 winds and storms. It is quite probable, in such 

 circumstances, that some of the birds will adopt, at 

 any rate temporarily, the habit of eating kinds of food 

 to which they have not been accustomed, but which 

 may be sufficiently palatable to be edible. For 

 example, a woodpecker searching for food among cacao 

 trees and probably attempting to extract an insect 

 from a cacao pod might easily be supposed to develop 

 a sufficient taste for the pulp of the cacao bean to 

 employ this as food during times of shortage of supply. 



Orange Oil in Italy and Jamaica. 



In Italy, after the jMessina earthquake, it became 

 speedily known that a very large part of the stocks 

 of orange oil at that place and at Reggio had been 

 destroyed, and it was thought that, as a consequence, 

 there would be a great scarcity of sweet orange oil, and 

 that prices would advance. Actually, the tendency of 

 the market has been the opposite to this, and prices 

 have been steadily falling. In the Semi- Annual Report 

 issued by Messrs. Schimmel & Co. in October last, it is 

 stated that careful investigations, undertaken for the 

 purpose of finding an explanation of the circumstance, 

 made it evident that a considerable industry in the 

 manufacture of new oil had gradually arisen. The cause 

 of this was that, owing to the repeated destruction of 

 the railway track, the use of the line, as soon as it 

 was repaired, for carrying supplies into the distressed 

 regions, and the conversion of railwaj' cars into 

 dwellings for the destitute survivors, the export of 

 oranges from Calabria was stopped, so that growers 

 employed their fruit in the manufacture of essential 

 oil, thus giving rise to a new source of supply. 



