182 D. d'emmerez de charmoy and s. gebert. 



Chloridea ohsoleta, F. This polyphagous insect of world-wide distribution, 

 commonly known as the American bollworm, is found here on a great variety of 

 plants, the chief being maize, tobacco, Hibiscus esculentus, Cajanus indicus, and 

 various other leguminous plants. It is also a serious pest of pelargoniums, destroying 

 the tender stems and flowers. 



Earias insulana, Boisd. The caterpillar is the spotted bollworm of India. It 

 is another cosmopolitan species, and its feeding habits in Mauritius appear to be 

 much the same as those of Chloridea obsoleta. It seems, however, to confine its 

 attacks particularly to Malvaceae, and is of rather common occurrence. Twigs, 

 leaves and flower-buds are attacked as well as the bolls. 



Platyedra gossypiella, Snd. The pink bollworm is one of the most serious pests 

 of cotton, and although it has not yet been observed on cotton in Mauritius, a few 

 moths have been bred from pods of Cajanus indicus and other Leguminosae of the 

 same type. 



Pyroderces { Anatrachyntis) simplex, Wlsm. The moth has been obtained from 

 larvae found in cotton bolls. 



Dysdercus spp. Of the cotton pests which are found here, the red cotton- 

 stainers, of which two species exist, are by far the most common, and are found on 

 all malvaceous plants, as well as on many others, growing along the coast. As 

 cotton-stainers have done considerable damage in cotton-growing centres, they can 

 probably be looked upon as our most serious potential pest. Dysdercus is known 

 to transmit several bacterial diseases. It has already done a good deal of damage 

 to cotton bolls at the experimental plantation of the Department, and is the vector 

 of an internal disease of the bolls similar to that described by Nowell and others in 

 the West Indies. 



Aphis gossypii, Glov. This green aphis is common on various garden plants 

 as well as on cotton. It is parasitised by a species of Aphidius, and is preyed upon 

 chiefly by a large ladybird, Chilomenes lunata, and by Syrphid flies. 



Saissetia nigra, Nietn., and Saissctia hemisphaerica, Targ. These two scale- 

 insects occur on various plants besides cotton. 5. nigra is found chiefl}' on Hibiscus 

 esculentus, rubber, mango and various Malvaceae. It is parasitised by two species 

 of Chalcids and by a fungus. These probably keep it in check, as it cannot so far 

 be reckoned as a pest. S. hemisphaerica occurs chiefly on citrus, guava (Psidium), 

 litchi (Nepheliuni) and Aristolochia acuminata. 



Achatina fulica. Though not an insect pest, mention may be made of this 

 large snail, locally known as " Couroupa," which also occurs in India and Ceylon, 

 whence it has been introduced here. It was responsible for a good deal of damage 

 to cotton seedlings, when the attempt was made to plant cotton on a large scale 

 in 1911. As the snails are very large, it is not difficult to have the land cleared of 

 them by hand-picking before planting. This should be done in the evening, as the 

 snail has nocturnal habits. Those met with in the daytime are generally found 

 hiding in dark places, or are in copulation. They are most active after the first rains 

 have set in and after sunset. 



Tobacco. 



Extensive cultivation of tobacco has recently been tried by this Department, 

 and as the results obtained have been very satisfactory, it is thought that tobacco 

 growing may rank among the chief of our minor industries. The variety tried is 

 that which is extensively grown in the island of Reunion. The yields have been 

 satisfactory, and the prepared cigarette tobacco has sold rapidly. Planting is being 

 encouraged by the Department of Agriculture, which is doing everything it can in 

 order that tobacco cultivation may be carried out on a large scale. 



