314 



of tlie plants bore four seed-pods, wliile upon tlie other were two dozen 

 of these pods, eacli containing perfect seeds. The " march of progress "' 

 liad obliterated the remaining- three plants which I had inclosed in 

 sacks, the plants having been uprooted and burned in order to give 

 place to an olive grove. In the case of the two i)lants above mentioned, 

 pollination had evidently been brought about by the repeated blowing 

 of the sacks against the expanded flowers. In nature, of course, no 

 condition like this exists, and it tlierefore seems very evident that, 

 but for the kindly office performed by the Pronuba, Yucca whipplei could 

 not exist. 



THE COCOANUT AND GUAVA MEALY-WING. 



(Alein-odiciiti cocois Curtis.) 



Fig. 39. — Aleurodicus cocois Curt.: a, adult female; 6, side view of abdomen; c, dorsal view of 

 .same; d, antenna; e, head from side;/, costa of front wing ; g, rosta of liiud wing; h, tarsus; 

 i, pulvillus; k, adult male; I, (^laspers — a, A; enlarged; other.s still more enlarged (original). 



Under his well known pseudonym "Ruricola," John Curtis described 

 in the Gardeners^ Chronicle for May 2, 1845, a new Aleyrodid from the 

 leaves of the Cocoanut trees in Barbadoes. The specimens were sent him 

 by Sir Robert Schomburgk, who stated that to its work is attributed a 

 widespread disease of the cocoanut which at that time threatened to 

 destroy all of the trees on the island. The disease showed itself after the 

 fatal hurricane of 1831, and at the time of writing there m ere few trees not 

 affected by it. Cocoanut plantations which formerly yielded an income 



