COMMON THRIPS. 31 



CHAPTER CIX. 



Common Thrips. 



(Thrifts tabaci, Lindeinann.) 



Order : Thysanoptera. Family : Thripidce. 



This is a singular little insect, characterized by long 

 narrow membranous wings with long ciliae or hairs, as 

 shown in our enlarged figures. The pupa and perfect 

 insects are very active, and almost too minute for a popular 

 description ; but when a plant or flower is badly affected, 

 the whole appears to be covered with tiny, narrow, dark 

 specks, which can hardly be determined with the naked 

 eye. The species under notice is an introduction from 

 Europe, and has long been known in England and elsewhere 

 as one of the gardener's worst enemies, especially to plants 

 growing under glass. The eggs are deposited on the food 

 plant, which is, however, by no means limited to any 

 particular kind. 



Thrips are the greatest of all troubles to the rose-growers 

 of this State, and appear in countless millions as if by 

 magic. In Europe, an insect known as Thrips cerealium 

 is a great pest of the wheat-grower, and in some instances 

 has been known to do a vast amount of damage to the 

 crops. 



Other thrips, known as Gall-making Thrips, have been 

 described by Mr. Froggatt. These singular bladder-like 

 galls were found on the leaves of Eugenias and other ever- 

 green plants. Our plate shows a rose bloom and bud 

 absolutely deformed through the attacks of these tiny 

 creatures. They are equally severe on apples and other 

 blossoms, and frequently prevent the fruit setting. 



In Russia, Dr. K. Lindemann, in his studies of these 

 insects on the tobacco plant, found the life cycle to be as 

 follows : — Development of egg, 10 days ; development of 



