Mytilaspis. 79 



from each marginal indentation. There are three or four similar spine-like 

 processes on the lateral expansions of the three preceding abdominal segments. 

 Circumgenital glands in five groups : the median represented by a chain of 

 about eight orifices, the upper laterals with twelve to sixteen, and the lower 

 with nine or ten. There are numerous tubular spinnerets ; viz., twelve rather 

 large cylindrical ducts opening by conspicuous oval pores on to the margin ; 

 and six vertical series of small and inconspicuous capitate ducts opening on 

 the dorsal surface of the pygidium. The margins of the abdominal segments 

 are studded with similar small spinnerets. Anal aperture close to base of 

 pygidium. Genital aperture immediately below the grouped glands. Length 

 I to 1*50 mm. 



Adult male unobserved. I was unable to rear any perfect males from my 

 Ceylon specimens. 



Male larva of second stage {fig. 7) similar in form to adult female, but much 

 smaller. Shortly before pupation the ocelH of the image are indicated by two 

 dark spots on each side of the head, each pair connected by a dark band. 



Young larva minute, very active, almost colourless. 



Eggs white, disposed irregularly beneath the scale. 



There are at least three successive broods of this species in the course of 

 the year. In fact, as is the case with many of our Ceylon scale insects, there 

 seems to be an uninterrupted series of broods. 



Habitat on fruit {fig. i) leaves and stems of orange and other species of 

 citrus. When occurring on the leaves, it apparently prefers their upper surface. 

 I have also found it on the leaves of Toddalia aciileaia, Punduloya. 



A very widely distributed species. Found almost wherever any species of 

 Citrus is cultivated. I have examples from America, New Zealand, Australia, 

 and Madeira. It is also commonly found on Maltese and other Continental 

 oranges sold in England. I have examined such specimens, and have found 

 the scales to contain living insects and numerous eggs, proving how readily the 

 pest may be introduced into new countries. It is therefore not surprising that 

 this species has become almost world-wide. 



Its presence in large numbers upon an orange tree is generally indicated by 

 an unhealthy appearance of the fruit and foliage. A wash of kerosene emulsion 

 (as described in the chapter on insecticides) will be effective in checking the 

 pest if applied when the young larvae are seen to be on the move. The older 

 insects are too well protected by their scaly covering to be much affected by 

 this treatment. 



