76 



It is claimed that Rhizohius lophanthcB was probably in California 

 some years before it was introduced by Albert Koebele from Austra- 

 lia, having evidently been introduced accidentally. It was noticed 

 among- the mountains north of Pomona, Cal., in 1891, and in San 

 Diego the following j^ear. Some notes on this and related species 

 have been furnished by Prof. John B. Smith in an article entitled 

 " Scale Insects and their Enemies in California," published in Bul- 

 letin Xo. (3, n. s., of the Division of Entomolog}^ pages 46-48. There 

 can be no doubt that the efi'ectiveness of some of these ladybirds has 

 been handicapped hy the somewhat careful methods followed by 

 growers of citrus fruits in California in spraying and fumigating 

 scale-infested orchards. Nevertheless, it is extremely doubtful if any 

 of these ladybirds, after having once obtained a foothold, could be 

 exterminated by fumigation or spraying, as some atfect to believe. 

 If any species have died out, it has probably been due chiefly to 

 natural causes, such as insect and other enemies, and climatic condi- 

 tions deleterious to their development. 



LOCUSTS, MALARIA, AND MOSQUITOES IX THE TRANSVAAL. 



We have just finished a most successful locust campaign. I do not 

 know how many swarms of locusts we have killed, but it will evi- 

 dently run into thousands. In one little valley about 20 miles wide 

 and 20 miles long our official force killed about 1,500 swarms, varying 

 in size from 10 by 12 feet up to swarms occupying an area of 5,000 

 square yards. In this valley there were also 30 farmers working on 

 their own farms, and I would not care to estimate how many locusts 

 were killed. From evidence given by old residents and by the natives 

 I find that this has been one of the worst locust years in their memory. 

 They all agree that if these swarms had not been destroyed nothing 

 would have been harvested in this locality, whereas at present all the 

 damage could be easily compensated by a $5 note. The Kaffirs are 

 esj^ecially keen on this question of destruction, and have turned out 

 in hordes to aid the district locust officer. Our success in this valley 

 is one of the many successes which Ave have had throughout the 

 infested districts of the colony. We are placing our main reliance 

 upon a strong arsenical spray. The spray consists of 1 pound of 

 arsenic, half a pound of carbonate of soda, 1 ])Ound of sugar, and 1(> 

 gallons of water. These chemicals are boiled together so as to make, 

 the solution arsenite of sodium, which is sweetened by the sugar. In 

 order to show you how etfective this is, I need only cite one in- 

 stance of a farmer who noted a swarm of fully grown " voet- 

 gangers *" — that is, grasshoppers in their last stage before obtaining 

 Avings — Avhich was 200 yards long and 50 yards Avide. These locusts 

 were advancing doAvn a hill toAvard his " mealies.'' (The term 



