116 FLORIDA FRUITS ORANGES. 



and much sooner from the leaves than from the rind of 

 the fruit. 



The adult mite is slightly darker than the young in 

 color, and becomes more opaque as it grows older. No 

 sexual differences have been distinguished, nor has the act 

 of coupling been observed. 



Owing to the difficulty of confining the mites without 

 interfering with the conditions necessary to their existence, 

 it has not been possible to determine the duration of their 

 lives. It is, however, safe to conclude that they live sev- 

 eral weeks after reaching the adult stage. The number 

 of eggs deposited is also uncertain, but it is probably not 

 abnormal, and the enormous populousness of their colonies 

 must be attributed to rapid development and comparative 

 immunity from enemies and parasites, rather than to ex- 

 cessive fecundity. 



Food. This evidently consists of the essential oil which 

 abounds in all succulent parts of the orange and its con- 

 geners, and which the mites obtain by penetrating with 

 their sucking beaks the cells that lie immediately beneath 

 the epidermis. That they do not feed upon the chloro- 

 phyl is shown by the color of their intestinal contents, 

 which has no tinge of green but a clear yellow, unmistak- 

 ably indicating the source from which it came. 



Wandering Habits. While engaged in feeding, the mites 

 remain quiescent for a length of time varying from a few 

 minutes to half an hour. They then move on a short dis- 

 tance and again become motionless. If disturbed they 

 have a habit of erecting themselves upon the leaf, cling- 

 ing to its surface only by the anal proleg. 



When dissatisfied with their surroundings, or when food 

 becomes scarce, they wander restlessly about, and undoubt- 

 edly travel to considerable distances. Their rate of prog- 

 ress on a smooth surface is quite rapid, and amounts to ten 



