Tenth Annual Meeting 



85 



to certain rules and restrictions which have been laid down by 

 foreign governments to guard against the introduction of this 

 little pest. If we are going to eradicate it, we must not rely 

 upon natural means. It is a fact that there are a number of 

 parasites which feed upon this scale. It reminds me of the old 

 couplet : 



"The little fleas, that do us tease, 

 Have other fleas to bite 'em, 

 And these in turn have other fleas, 

 And so on ad infinitum." 



At the same time, we cannot apply that philosophy in this 

 case with any degree of satisfaction. While these little fellows 



Fig. q. — ^True pnxuMe. Aphelinus Jiaspidis, Howard, of the San Jose scale. 

 (After Howard in Bulletin 5. new series, Div. Ent., U. S. Dept. Agr.) 



are scratching the backs of the San Jose scales, the latter are 

 going on just the same, sucking the life out of our trees. 

 One of these little insects (see Fig. 9) that prey upon the scale 

 penetrates the scale and deposits an egg underneath it. The 

 egg hatches out a worm, which feeds upon the scale and de- 

 stroys it. Still, while he is destroying one, the old mother 

 scale may have escaped and produced larvae that will develop 

 five or six hundred. So we have an unequal balance in this 

 particular case, at least, so far as natural enemies of the scale 

 are concerned. I have been studying this question in the south 

 carefully. In California, it is said that the San Jose district 

 has almost been cleaned of this scale. As a matter of fact, I 



