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experimental stage of the work. Even when the beneficial insect has 

 been successfully established in a country, it is by no means certain 

 that it will thrive. There may be climatic or other conditions against 

 it. In that case, all we can do is to try another insect. Occasional or 

 even repeated, failures should not discourage the repetition of the 

 attempt. The value of a single success will far outweigh the cost of 

 many failures. In the course of such experiments the causes of failure 

 will in time be ascertained, and improved methods be employed. The 

 freezing method recommended by Mr. Koebele seems to be rather an 

 uncertain one, and has led to many disappointments. I am inclined to 

 hope for more satisfactory results from the employment of ' Wardian 

 cases,' as suggested to me by Mr. Lounsbury. In these the 

 insects will remain active and be supplied with food. There 

 are certain obvious dangers connected with this method, such 

 as is possible introduction of the insect pest upon which the • lady- 

 birds' have been supported during the voyage. For this reason the 

 business should be conducted under the supervision of trained entomolo- 

 gists only. In choosing the food supply, an insect that already occurs 

 in the country to which the lady-birds are consigned should, if possible, 

 be selected* But, under any circumstances the imported beetles should 

 not be liberated immediately, but should be Iransferred to fresh breed- 

 ing cages and supplied with local food, and the cage in which they ar- 

 rive should at once be thoroughly disinfected. In sending stocks by 

 Wardian case, the larvae of the beetles may with advantage be included. 

 These will complete their transformations during transit, and are more 

 likely to survive the voyage than the adult insects. 



There are other natural enemies of the Coccidae that may some day 

 be advantageously employed in the same way. Amongst the two- 

 winged flies (Diptera) we find the Lestophonus iceryae, which attacks 

 the ' Fluted-scale.' Nearly every species of sc le insect is subject to 

 minute internal parasites belonging to the wasp family (Hymenoptera). 

 The family Neuropter;i supplies the ' Lace-wing flies,' the Wvne of 

 which are known as ' Aphis-lions,' from the voracious way in which they 

 feed upon Aphides and scale-insects. Even the butterflies and moths 

 (Lepidoptera) provide a few coccid- eating species, such as the caterpil- 

 lars of the butterfly Spalgis epius and of several moths ot the genus 

 Eublemma. The 'Lady-birds' are included in the family Coleoptera. 



Besides natural enemies belonging to the animal kingdom, scale 

 insects are subject to diseases belonging to the vegetable world. There 

 are several parasitic fungi that render great assistance in reducing the 

 numbers of our Coccid pests. In Ceylon during the wetter months of 

 the year, the ' green bug ' (Lecanium viride) dies off to a large extent, 

 attacked by a greyish mould which, after killing the insect, spreads 

 outwards as a delicate fringe of interlacing whitish threads. A bright 

 orange-coloured fungus (Septoria? sp.) is useful in checking the increase 

 of Fiorinia fioriniae and Ghionaspis biclavis on the tea plant, and Aspi- 

 diotus aurantii on orange trees. A very similar fungus (Sphaerostilbe 



* In a recent consignment of 1 lady-birds' received from the Cape of Good 

 Hope, the cochineal insect (Coccus cacti) was very judiciously chosen for the 

 purpose. This insect is practically confined to the 'Prickly Pear' cactus, and 

 is iherefore not liable to become a pest. 



