Toughening of the film may be effected by well shaking up the light 

 oil with raw Unseed oil just before application, though whether the 

 advantage gained is sufficient to justify a strong advocacy of its use 

 is uncertain. 



In testing the ejficacy of crude carbolic acid, an emulsion was made 

 as follows :— Crude carbohc acid containing about 15 per cent, phenol 

 was heated to 212° F,, finely pulverised resin was added, and the mix- 

 ture boiled till all the resin was dissolved. Caustic soda was then 

 added and the mixture kept at 212° F. for about 10 minutes, or imtil 

 a perfectly dark emulsion without sediment was obtained, the mixture 

 being thoroughly stirred from the time the resin was added to the end. 

 It is claimed that 1 part of this mixture in 5,000 parts of water 

 containing mosquito larvae will kill them all within 5 mii*utes, or in 

 30 minutes when used in the proportion of 1 to 8,000. The author 

 did not obtain results as good as these, though much better ones were 

 arrived at when using an emulsion of light oil. 



Experiments with iron and copper sulphates, potassium ferrocyanide, 

 and other well-known substances gave negligible results. 



When there is no access of fresh water, an emulsion that contains 

 nearly all the light oil that the emulsionising agent can carry and that 

 has no needless water may be used in the proportion of 1 in 32,000. 

 The following are rehable formulae : — (1) Soft soap, 100 parts ; light 

 oil 440 parts ; water, 100 parts ; caustic soda, 80 parts ; the light 

 oil being added after the other substances have been heated together 

 to 212° F. ; the resultant substance is a thick jelly that may be liquefied 

 by dilution with water. (2) Soft soap, 20 parts ; light oil, 50 parts ; 

 giving a thick, jelly-Hke soap. (3) Castor-oil 50 parts ; caustic soda 

 (sat. sol. of 98 per cent, caustic soda), 15 parts ; water, 20 parts ; 

 light oil, 170 parts ; the castor oil and caustic soda being first boiled 

 together to make an even yellow-green soap, to which the fight oil 

 may then be added ; the resulting emulsion is a clear fiquid that keeps 

 well. 



Owing to the shortage of potash, soft-soap is becoming costly, and 

 other emulsionising agents are beuig experimented with, good results 

 having been obtained with resin, neatsfoot-oil, and whale-oil. The 

 last is the cheapest and is used for work in military camps, but it is 

 sometimes difficult to saponify it by the means available. 



Ticks affecting Big Game. —11th Ann. Rept. Dept. Agric. Province of 

 Saskatchewan for Sixteen Months ended SOth April 1916, Regina, 

 1916, pp. 232-235, 2 figs. [Received 3rd October 1918.] 



Dennacentor albipictus (moose-tick or wood-tick) is not generally 

 considered to be of economic importance, but of recent years it has 

 been recorded as an important pest of horses and cattle, especially 

 the former. Reports from California, Montana and Oregon state 

 that in districts infested by D. venustus (Rocky Mountain spotted- 

 fever tick) the combined attack of these two species, together with a 

 shortage of feed in spring, often causes the death of numbers of horses 

 in cases where they are not properly cared for. 



D. albipictus has also been recorded from Manitoba on the moose, 

 and is found also on the wapiti and horse, being a common species 



