10 



during the time that the trees are leafless upon evergreen trees in 

 the vicinity of water courses, the removal of such trees would probably 

 render the locality imsuitable as a permanent fly belt. 



In conclusion it is pointed out that no method of definitely checking 

 tsetse is known, and any measures taken must be in the nature 

 of experiments. The necessity for beginning dipping experiments in 

 relation to tsetse-fly as quickly as possible is emphasised, 



Dunn (L. H.). The Tick as a possible Agent in the Collocation of the 

 Eggs of Dermatohia hominis. — Jl. of Parasitology, Urbana, III., iv, 

 no. 4, June 1918, pp. 154-158. [Received 16th October 1918.] 



The case is recorded of man being attacked on several occasions 

 by ticks in the interior of Panama, the wound caused by the bite 

 of the tick being discovered later to be infested with a larva of 

 Dermatobia hominis, which had evidently hatched from an egg deposited 

 by the tick during its attack. The tick concerned was in all probability 

 Amblyomma cajennense, which has a variety of hosts and attacks man 

 and all classes of both domestic and wild animals with equal freedom. 

 The incrimination of ticks in the dispersion of eggs of D. hominis 

 opens up a new field. Previous writers have adduced more or less 

 convincing evidence that a mosquito, Janthinosoma (Psorophora) lutzi, 

 is the active agent in this dispersal, but it has never been proved to 

 be the sole carrier. Among many mosquitos collected at the time 

 and in the vicinity of the above-mentioned attacks, J. lutzi was not 

 found. 



Cory (E. N.). The Control of House Flies by the Maggot Trap.— 

 Maryland State Coll. Agric. Expt. Sta., College Park, Bull. no. 213, 

 February 1918, pp. 103-126, 12 figs. [Received 15th October 

 1918.] 



The subject-matter of the first part of this bulletin has already 

 been noticed [see this Revieiv, Ser. B, iii, p. 134]. 



In the years 1914, 1915 and 1916 the average percentage of maggot 

 destruction was 95*8 per cent. The reduction in fly prevalence in 

 1914 was 76 per cent., but in 1915 and 1916 this was not so marked, 

 the apparent discrepancy being probably due to the presence of 

 additional fly breeding sources and the difficulty of obtaining accurate 

 results on fly reduction. Modifications of the traps as dictated by 

 experience have evolved a trap that is practical for the farm producing 

 large quantities of manure daily. 



The close packing of manure, the watering of the heap and the return 

 of leached materials to the manure tends to conserve its fertilising 

 value, and the labour involved is only slightly greater than that 

 required to dump the manure in a heap. The saving in fertiliser and 

 the destruction of a large percentage of the flies, particularly on 

 isolated farms, will more than repay the cost of construction and 

 operation. 



A table shows the seasonal prevalence, from July to October, of 

 the flies trapped, including : — Musca domestica, Muscvrm stabulans, 

 M. assimilis, Pollenia rudis, Phormia regina, Lucilia caesar, L. sericaia, 

 Calliphora vom,itoria, Graphomyia maculata, Ophyra leucostoma. 



