CITRUS FRUIT INSECTS IN MEDITERRANEAN COUNTRIES. ll 



NATURAL ENEMIES. 



The most abundant parasite of this scale is a species of Aphelinus. 1 



Two or three species of Coccinellidse have also been seen feeding on 



the scale. These are the same species as those already given for the 



black scale. 



THE PURPLE SCALE. 2 



Lepidosaphes beckii Newm. 



DISTRIBUTION AND INJURY. 



The purple scale was seen in most of the citrus sections of Spain and 

 Italy. It is found very generally in the Valencia orange section and 

 in the Sicilian lemon section. Not infrequently the numbers are 1 

 sufficient to do injury to the trees. This consists of the killing of a 

 few branches, or a portion of one side of the tree. (PI. V, fig. 1 .) The 

 scale is also more or less common on the fruit. It occurs in many 

 places in Sicily in only scattering numbers, and in small areas, or, on 

 a few trees, in large numbers. This is about the status of the scale in 

 California and Florida and the Valencia section of Spain, but on the 

 island of Sicily it is less injurious than in any of these three localities^ 



LIFE HISTORY. 



The purple scale deposits from 40 to 80 eggs, which are well inclosed 

 by the scale covering above and a lighter, cottony covering beneath. 

 The eggs hatch in 15 to 20 days in summer. Most eggs and young will 

 be found in the spring — May and June — and another large batch in 

 August and September. At all other seasons eggs will be found, but 

 usually in less numbers. The period of development from hatching 

 to egg-laying ranges from one and one-half months in summer to 

 three months in winter. 



NATURAL ENEMIES. 



The purple scale has been considered a pest of little economic 

 importance in Mediterranean countries, and this has been accounted 

 for through the efficient work of parasites. The writer takes excep- 

 tion to both of these counts. Just as severe injury has been seen from 

 this scale in Spain as in California or Florida. And further, what 

 natural enemies are keeping it in check ? Hitherto, so far as known, 

 no internal parasite has been reported from the purple scale in Sicily. 

 Dr. Martelli was informed by the writer that he had seen evidence of 

 Aspidiotiphagus citrinus attacking the purple scale, but the observa- 

 tion was questioned on the ground that the scale was Lepidosaphes 

 ulmi and not L. beckii. Of course, the parasitized scales were not 

 positively identified at the time. Later Aspidiotiphagus citrinus 



1 This species appears to be A. diaspidis, but its identity, according to Prof. Silvestri, of Portici, is some'' 

 what questionable. 



2 Spanish, Serpeta; Italian, Pidocchio a virgola; Sicilian, Pidocchiu. 



51981°— Bull. 134—14 3 



