October, 1910.] 



811 



Plant Sanitatiotii 



vascular bundles, but no doubt other 

 peculiarities will be developed as the 

 study of the organism progresses. 



A very considerable part of the 

 banana holdings in tropical America are 

 iu the hapds of Americans, and as we 

 also consume the greater part of the 

 product, it is highly important to pre- 

 vent such destruction of the plantations 

 as shall lead to a loss of American capi- 

 tal and an'increase in the price of this 

 important food product. 



ENTOMOLOGICAL NOTES. 



By E. Ernest Green, 

 Government Entomologist. 



African Snail (Achatina Fxdica.) 



Since the publication of my report, I 

 have received a very fine specimen of 

 the shell of this snail. It is considerably 

 larger than any seen during my visit to 

 Kalutara. It measures just five and 

 three quarter inches in length : but even 

 this monster, in life, would scarcely 

 touch the one-pound-two-ounce speci- 

 mens that I was led to expect from 

 native reports. 



It appears, also, that the snail still 

 occurs in the Rozelle (Watawala) dis- 

 trict where it was originally introduced. 

 It attracts very little attention there 

 and does little or no damage. It is 

 probable that the cold wet climate of 

 the Ambagamuwa Valley is not condu- 

 cive to its rapid increase. Specimens 

 received from that district are distinctly 

 smaller than those observed near Kalu- 

 tara. 



A correspondent sends me a copy of 

 "The New York Hearld " (Continental 

 Edition) of August 28th. It contains a 

 short account (with the usual lurid 

 headlines) of the outbreak at Kalutara, 

 and reproduces the best picture that I 

 have yet seen of a cluster of the snails 

 upon a coconut stem. It is superscribed 

 as representing " Snails Destroying 

 Trunk of Coconut Tree." 



A Trypanosome Conveyed by Blood- 

 Sucking Bugs. 



In a recent number of this Journal, 

 (April 1910, p. 323), I gave an account of 

 the sanguinary habits of a large Redu- 

 viid bug (Conorhinus rubrofasciatus) in 

 Ceylon. It has recently been discovered 

 that a Brazilian species {Conorhinus 

 megistus) harbours a Trypauosome and 

 infects its human victims with a serious 



disease allied to the notorious ' sleeping 

 sickness ' of Africa. It is to be hoped 

 that our Ceylon representative of the 

 insect has no such evil communications 

 to convey. 



Beetles Breeding in Tapping 

 Wounds on Castilloa Rubber. 

 A correspondent sends me a number 

 of small Nitidulid beetles, and their 

 larvae, found in the tapping wounds on 

 a Castilloa rubber tree, where they were 

 associated with a frothy lather exuding 

 from the cuts. These insects do not 

 attack living trees, but— in this case- 

 must have been attracted by the smell 

 of the putrid sap. Mr. Lefroy, in his 

 book " Indian Insect Life," remarks of 

 the Nitidulitlte :— " Though of no eco- 

 nomic importance, they are common in- 

 sects and will be readily observed on 

 crop plants under circumstances that 

 would, in the absence of careful observa- 

 tion, give rise to the suggestion that 

 they were themselves the originators 

 of damage, whereas they are essentially 

 the followers of decay." This same 

 species of beetle has been sent to me 

 before, associated with a disease in the 

 stem of a mulberry tree. The presence 

 of such beetles under the bark of a tree 

 may usually be taken as an indication 

 of some fungal or bacterial disease. 



Paddy Bug. 

 The so-called ' Paddy Fly '—more cor- 

 rectly described as the 'Paddy Bug'— 

 (Leptocorisa acuta) was observed to be 

 present in enormous numbers on the rice 

 plots at the Maha Iluppalama Experi- 

 ment Station, and will seriously affect 

 the yield. To obtain some idea of the 

 actual loss attributable to the work of 

 this insect, I am arranging tor the en- 

 cl osure of a small area containing a de- 

 finite number of plants which will be 

 protected by a screen of mosquito-nett- 

 ing. An adjoining area of the same size 

 and contents will be staked off, but 

 remain unprotected. The produce of 

 the two plots will then be compared. 

 There are large areas of waste land, 

 covered with wild grasses, surrounding 

 the rice plots, which doubtless accounts 

 for the prevalence of the insect. To 

 control this pest it is essential that it 

 should be deprived of food in the inter- 

 vals between the rice crops. It is 

 then dependent upon the natural grasses. 

 It will be sufficient if these can be pre- 

 vented from flowering, as the insect 

 obtains its nourishment from the unripe 

 seeds of the grass. The periodical burn- 

 ing off of the grass land, at compara- 

 tively short intervals, would answer the 

 purpose, 



