Remedial Measures and Insecticides. xxv 



seems to be rather an uncertain one, and has led to many dis- 

 appointments. 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 the 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 entomologists 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 transferred to fresh breeding 

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

 arrived 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 LestopJionits iceryce, which 

 attacks the ' Fluted-scale.' Nearly every species of scale insect is 

 subject to minute internal parasites belonging to the wasp family 

 {Hynieitoptera). The family Neiiroptera supplies the ' Lace-wing 

 flies,' the larvae 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 {Lepidopterd) provide a few coccid- 

 eating species, such as the caterpillars of the butterfly Spalgis epins 

 and of several moths of the genus Eiibleinma. 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 assist- 

 ance in reducing the numbers of our Coccid pests. In Ceylon, 

 during the wetter months of the year, the ' green bug ' {Lecanunn 

 viride) dies off to a large extent, attacked by a greyish mould 



* In a recent consignment of '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 therefore not liable to become a pest. 



