205 



Notes on Hevea confusa Hemsl. 



Til Vol. TI No. 4 of the ■' Gardens Bulletin" a description was 

 .given of Ilevea confu.^a which is considered to be an undesirable 

 neighbour to Ilevea- hraaUensis, although in general appearance it 

 is not easy to tell tlieni a])art. In reference to the above article 

 the following letter has been received from Prof. J. B. Harrison, 

 C.M.G., Director of Agriculture, Demerara. It would appear that 

 the plants at Singapore were raised from Prof. Harrison's seeds. 

 •• Y'our records will show you that about 1910^1911 I wrote to 

 your gardens seeking information about the seeds of Ilevea confusa 

 sent there from here about 189<S-19()0. Will you kindly inform Mr. 

 B. J. Eaton that liis analytical results on the ruilvber fully confirm 

 those obtained here about 1910-1911 during tlie large scale tappings 

 of //. confum trees in our forests. We showed the confum rubl)er 

 at the Rulxber Kxijiibition of 1911. When the soft rub<l)er is kept 

 for a length of time it very slowly gains resiliency and finally 

 resembles slightly tacky or very inferior rubber from //. hrasi- 

 liensis. Towards the end of 19^1 the//, confusa ru]>ber was valued 

 in the U. 8. A. at approximately G'G% of the then price of hard 

 para rubber. Some hundredis of pounds were said to have been 

 used in the factory tests. It was I believe, fijially used as an in- 

 gredient in mixings for vulcanite. 



" II. co?ifusa has proved to be a most objectionable tree. Ex- 

 perience has shown that cross-fertilisation between //. confusa and 

 H. brasiUensis readily takes place but, worst of all it appears in the 

 Ouianas to be the forestral host plant of the organism giving rise 

 to the leaf-disease of Para rubber, which disease has ]n'actically put 

 an end to the chances of successful Para rulj'l)er cultivation in 

 French and British Guiana." 



A small seedling has been ])lanted in the Botanic Gardens near 

 the Herbarium and far removed from any Ilevea brasiliensis. 



T. F. C. 



A Pest of Lima Beans, 



A beetle which has Ijeen very troublesome in eating the leaves 

 of the Lima Bean plants was submitted to the Kev, G. Dexter Allen 

 for determination. In his reply Mr. Dexter Allen says: — 



" The insects you sent are Phytophagous beetles of the Section 

 Eupoda and almost certainly belong to the Genus Cryptocej^halus, 

 the s])eoies is very probahly un-named as yet. The genus has very 

 numerous representatives in the Indo-Malayan Insect Fauna, and 

 this is al)out the smallest species of the genus I have seen. These 

 beetles generally feed on the leaves at night and are therefore 

 ditfieult to exterminate. I have often collected Phyto])hagous 

 ])eetles, never so small as these however, with some one carrying a 

 hurricane lamp for me. 'Sjiraying the leaves is frequently useful, 

 nicotine and arseniate of soda might be tried experimentally." 



T. F. C. 



