256 



October 16, plants in this same garden were found to be infested with 

 Aphides, and the top of one of the most thickly populated was removed 

 and placed with living plants in a breeding cage. With the change to 

 a warmer environment, the insects became more active, and instead of 

 of a single species, as at first supposed, there were found to be four r 

 three Aphides, viz, Siphonophora near erigeronensis. Aphis near planta- 

 ginis, at the time being studied on carrot and Portulaca, Nyzus maha- 

 leb, and a minute Thrips, their relative abundance being in the order in 

 which they are here given. All three species of plant lice, and the 

 Thrips, developed on the Salsify and remained upon it for several weeks, 

 showing that their occurrence on plants in the garden was not acci- 

 dental.— [F. M. Webster, December 12, 1889. 



AN EGYPTIAN MEALY BUG. 



We are indebted to our esteemed correspondent Mr. D. Morris, of the 

 Eoyal Kew Gardens, for a copy of a letter from Mr. E. W. Blunfield of 

 Alexandria, Egypt, buring the past four years the gardens in Alex- 

 andria have been infested by a Coccus which destroys all of the trees 

 and is causing the greatest alarm. It first appeared four years ago when 

 Mr. Blunfield noticed it in quantities on the underside of the leaves of the 

 Banyan tree, but it soon spread with extraordinary rapidity and some 

 of the most beautiful gardens of the city full of tropical trees and shrubs 

 have been also destroyed. A breeze sends the cottony pest down in 

 showers in all directions. It seems to attack almost any plant, but the 

 leaves of Ficus ntginosa and one or two other kinds of fig seem too tough 

 for it and it will not touch them. He states that it seems almost im- 

 possible for a few horticulturists to try to eradicate this pest while their 

 indifferent neighbors are harboring hot-beds of them, and there will have 

 to be some strong measures taken by law to put it down. 



Mr. Blunfield sent specimens which were referred to Mr. J. W. Doug- 

 las, one of the most prominent British students of Coccidse, who upon 

 cursory examination decided that it was a species of Dactylopius. At 

 the time of this writing Mr. Douglas has not had time to examine it 

 with sufficient care to determine the species. We have written advis- 

 ing the use of one of the resin washes which have proved so effectual 

 against Icerya in California, and have mentioned particularly the one 

 given on page 92 of the current volume of Insect Life. 



A CASE OF EXCESSIVE PARASITISM. 



The frequency with which the Black Walnut is defoliated by the larvae 

 of Datana ministra has often been a source of regret to admirers of that 

 beautiful and majestic tree. Every autumn, throughout the Western 

 States, September finds many trees as devoid of foliage as in midwinter,, 

 the fruit hanging to the naked twigs with the very air of disconsolation. 

 Trees in the forest do not appear to suffer, the caterpillars seeming to 



