Vol. Ill No. 1'91. 



THE AGRICULTUKAL NEWS. 



203 



>inany years. Its recognition in Mauritius, however, extends 

 back over a period of only five or six years, and there seems 

 a very strong probability that this insect was introduced into 

 Mauritius in shipments of s■ug^^•cane ior planting purposes. 

 Other hardbacks related to P/ii/tali(.-< onit/ii. which might be 

 transported in the fame way are Lachnosterna patruitn in 

 8t. Kilt.«, and Lac/inosterna sp. in Antigua. The amount of 

 damage done by these two insects is not known, but it is 

 possible that if transported to a new locality they might 

 become serious pests. In St. Croi.x (Danish West Indies), 

 one of the rhinoceros beetles, Sti-'iti'jus titanns, occurs as 

 a serious pest in certain years. This is an insect wliich, 

 under normal conditions, is a scavenger in its habit of feeding, 

 but it has adapted itself to feed on living plant tissue 

 under the conditions existing in St. Croix. The insect 

 tunnels into the base of the plant, and to some distance above 

 the ground-level; but its tunnels are so large that there 

 should be no chance of its escaping unnoticed in the case of 

 sugarcane cuttings. It might easily escape detection in 

 soil, however, if this were used for packing sugarcane. The 

 •same might be said of the root borers Diaprejies ahhrevlatux 

 in BarViados, and Exophthalmus emriens in the Leeward 

 Islands. These insects attack the underground portion of 

 the stem, eating out the interior, but they do not extend 

 their tunnels into the cane above the ground level. The 

 modern method of packing sugar canes for planting in damp 

 charcoal is always to be preferred to the use of soil for this 

 purpose. Not only do the canes arrive at their destination 

 in better condition, but the danger is avoided of shipping 

 soil inhabiting insects, which might become serious pests 

 under new conditions. 



Bacteria in the Banana. — A summary of a recent 

 investigation in America concerning organisms in the banana 

 and the bio-chemical change.-; that take place during ripening 

 is contained in the Experiment Statvjii Record, Vol. .X.WIII, 

 No. 6. In this it is stated that the inner portions of the pulp 

 of sound bananas are practically sterile, but that the regions 

 of the inner coats of the peel may be sparsely inhabited by 

 bacteria. These are held in check during the normally 

 ripening processes, but subsequently they find conditions 

 favourable to growth. Since the protective covering of the 

 fruit is able to resist the invasion of bacteria, the investigator 

 ■was led to believe that the most probable channel of entrance 

 would be the circulation of the plant juice, and suggests that 

 infection occurs while the fruit is still on the tree. This dees 

 not appear to have been entirely confirmed by experiment, 

 and seems to be well worth continued investigation. The 

 limited experiments with the organism of decay does not 

 justify the conclusion that it is a specific for banana tissue. 

 It can be said, however, that the bacillus readily produces 

 decay, and, to the extent of the trials described, exhibits 

 a marked tendency towards the specific character. 



With reference to the studies on ripening, the following 

 facts are of interest. It seems that one essential change 

 during the ripening of the banana is the conversion of starch 

 into soluble carbohydrates, which con.sist principally of cane 

 and invert sugars and dextrins. Maltose is not produced. 

 The enzyme amylase is present in the early stages of ripening 

 and persists even in the over-ripe fruit. No evidence of 

 the existence of dextrinase or lactase was obtained, but 

 a protease was present and oxidase was found during all stages 

 of ripeness investigated. Sucrase is present in the unripe 

 stage but is much more intense in the ripened fruit. 

 Alkalinity retards or inhibits its action. The hydrolysis of 

 ■ raffinose by banana tissue waa demonstrated conclusively. 



CASTILLOA RUBBER IN DOMINICA. 



The eighth quarterly tapping of Castilloa trees in the 

 Dominica liotanic < Jardens having recently been completed, 

 the Curator (Mr. .Joseph .Junes) has furni.shed this Depart- 

 ment with information embodying the results that have been 

 obtained. 



It was found that the average yield per tree in four 

 quarterly tappings during 1911 was for the twenty-one-year 

 old trees, 1 ft). 7 oz.; for the fourteen-year-old trees, tb. 

 27 oz.; for the thirteen ye^r-old ones, lb. .3 3 oz. During 

 1912 the corresponding yields were respectively &. lOf oz., 

 It). 1 oz., lb. 11 oz. 



The girth of the trees and the number experimented on 

 can be seen from the following table: — 



No. of trees. Age, years. Average girth -3 feet 



from around. 



1912. 



1911. 



1912. 



It will be observed that the yield was much greater 

 during 1911 than during 1912, though even during 1911 it 

 was very low. The species of Castilloa grown in Dominica 

 thrive well, particularly on the coast lands, but the above 

 tapping experiments would appear to indicate that these trees 

 cannot be recommended for extended cultivation. The 

 latex, however, is of good quality. Samples analysed at the 

 Government Laboratory, Antigua, contained about 86 per 

 cent, of caoutchouc and from 9 to 12 per cent, of resin, com- 

 pared with 93 and 47 per cent, of caoutchouc, and 3 to -1, 

 and -50 per cent, of resin, in samples of locally produced Para 

 and Funtnmia Afrk'.ma, respectively. 



Utilization of Hawaiian Products.— Dr. E V. 



Wilcox, Director of the Hawaii Experimental Station, has 

 recently sent to a firm of paper manufacturers in the United 

 States a supply of pineapple leaves, and this firm has made 

 a favourable report on the fibre produced from them. It is 

 found suitable for a kind of tough paper used for insulating 

 purposes. It has been proved that the fibre can be produced 

 with the machinery for making sisal fibre. Seventy pounds 

 of fibre to the ton of pine-apple leaves can be produced, 

 which at 14 tons of leaves would be 1,000 ft. of fibre 

 to the acre. At a profit of only one halfpenny a pound this 

 means £2 an acre for what is now waste. Dr. Wilcox is- 

 stated also to have received reports from manufacturers of 

 varnish in various cities, upon samples of kukuinut oil sent 

 from the Hawaii Experiment Station. They are to the effect 

 that it is far better than linseed oil for making varnish. 

 Honolulu at present imports -50,000 gallons of linseed oil 

 each year. Experiments are being made to produce a press 

 to extract the oil. (From the Journal of fhe Royal .^ckty 

 of ArU, May 2, 1913.) 



A copy of the Imperial issue of the Financkr and 

 Bulliouist has just been received. This publication constitutes 

 the largest penny daily newspaper ever published in 

 the United Kingdom. A page with illustrations is devoted 

 to a description of West Indian affairs and a large amount 

 of valuable matter is preset. :ed in connexion with industrial 

 progress in Canada, Australia, South Africa and othec 

 regions of the British Empire. 



