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Coceidae and Aleurodidae of Madagascar and Comoro Is. 
Dactylopius citri (Risso). 
Habitat: On stems of Tobacco (Nicotiana tabacum). Fenerive (E. Madagascar), November 1904. 
The examples were packed together in a large cavity in the stem of the food-plant formed by the 
accidental removal of a side-shoot. They. were all apparently immature and though not quite typical agree 
best with Risso’s Dactylopius citri; but the cereous covering had been almost entirely destroyed in the 
‚ aleohol, so that it was impossible to trace the external characters. 
This inseet is practically world wide in its distribution. In Northern Europe it is one of the 
' commonest greenhouse pests, and is so hardy that it has been met with on plants out of doors in Great 
"Britain during the winter months; southwards it is a recognised pest on the orange and various other 
species of Citrus etc. It has been recorded from Mauritius, Brazil and Australia; is a pest in the West 
Indies, North and South America; and has also been recorded from North and South Africa; and I have 
received it recently from the Canary Isles. 
Dactylopius virgatus var. madagascariensis n. var. Newst. 
Form of the adult female similar to the typical examples of Dactylopius virgatus (Ck11l.) but 
considerably longer and broader. There is also a marked difference in the relative length of the antennal 
segments (fig. 1). There was no secretionary covering present on any of the examples but this may have 
been dissolved by the alcohol in which the insects were preserved; neither was there any trace of the dark 
, markings so pronounced in the living examples of D. virgatus. 

The distinguishing features of D. virgatus' apart from the curious secretionary covering of the 
females, are the long: subcutaneous tubes attached to the circular spinnerets (fig. 2). In making the diagnosis 
of D. ceriferus I quite overlooked the true character of these organs, though I fully described their external 
form; this omission was due to the fact that I did not at that time stain my preparations, so that when 

! These notes are based upon the structural characters of my examples of D. ceriferus (Indian Museum Notes. Vol. III. 
p. 24. 1895) which has been sunk as a synonym of D. virgatus Ckll. I have not seen examples of Cockerell’s types and am 
therefore not in a position to judge as to whether the characters set forth in this paper are present also in his types. 
Voeltzkow: Reise in Ostafrika 1903—1905. Wissensch. Ergebnisse, Bd. II, 45 
