107 



Silvanus sunnamensis, L., and Latheticus oryzae, Waterh., generally 

 destroy grain only when it has been injured by primary pests, but they 

 are undoubtedly real pests of flour, biscuits and other products. It 

 is thought that T. castaneum {fermgineum) , which occurred in great 

 numbers, can be induced to attack grain. T. confusitm was very rare 

 in the samples examined. Trogodenna khapra, in the form of remains 

 of the larval stage, was found in wheat samples from Queensland, 

 but whether the species was established there or only infesting the 

 ship is doubtful. This is the species that has lately been causing 

 much damage to malt in England [R.A.E., A, ix, 143, 431 ; 

 X, 32]. Tenebroides manritanicus , L., has frequently been recorded 

 as injurious, but in the present investigations it was observed to be 

 merely predacious. Both beetle and larva devoured T. castaneum, 

 S. surinamcnsis and other beetles, as well as larvae and pupae of 

 Ephestia kuhniella, Z. If placed in flour in a glass bottle, the larva 

 makes long burrows through the flour, evidently searching for insect 

 prey. Cathartus qttadricoliis, Guer., Echocerus maxillosus, F., and 

 Anthicus elegans. Lea, are recorded, apparently for the first time in 

 this country. Of Tinea granella, L., formerly reputed to be a serious 

 grain pest, only a single individual was bred. 



A list is given of the HvTiienoptera examined, with notes on their 

 origin, and the Lepidoptera and Coleoptera with which they were 

 associated. The species hsted are the same as those recorded in the 

 preceding paper. 



Bagnall (R. S.) Dendrofhrips ornafus (Jabl.), a Species of Thy- 

 sanoptera new to the British Fauna. — Ent. MlJilv. Mag., London, 

 Iviii, 3rd Ser. viii, no 85, January 1922, pp. 18-19. 



Dendrothrips ornatus, Jabl., is recorded from Scotland on limes in 

 company with Bagnallia calcarata, Uzel. 



A[shby] (S. F.). Some Recent Observations on Red Ring Disease of 



the Coconut. — Agric. Nei&s, Barbados, xx, no. 508, 15th October 

 1921, p. 334, & no. 509, 29th October 1921, pp. 350-351. 



Further experiments have been carried out in Grenada on the 

 red-ring disease of coconuts, transmitted by the Nematode, Aphelenchus 

 cocophilus, Cobb [R.A.E., A, viii, 66, 411]. Tests showed that the 

 larvae all died after fifteen hours' desiccation, but it is thought that 

 the eggs may prove more resistant. The larvae are active in drops of 

 water, in which they progress at the rate of about 5 ft. an hour ; they 

 will ascend a vertical moist surface either with or without the attraction 

 of bait, and remain active in fresh water for at least a week. In sea- 

 water, or in a 2\ per cent, solution of sodium chloride, they were 

 active for three days, but many were dead after five days. A 5 per 

 cent, solution allowed sluggish movement for four days, and in 10 per 

 cent, salt they were dead within an hour. In a 10 per cent, solution 

 of sodium bicarbonate active movement occurred for two days. 



Various experiments in inoculation of healthy palms with diseased 

 tissue are described. The sensitiveness of the larva to desiccation is 

 an important factor in limiting the chances of infestation, as it is 

 improbable that living larvae would be present in fragments of tissue 

 dry enough to be blown up by wind. Scavenging insects or palm 

 weevils are far more likely to be the means of transmitting living 

 Nematodes or eggs from dead or dying trees, and such trees should 



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