53 



tree. The trees chiefly aflfected are set iu grove budded last fall, dormant and cut 

 off this spring. They have made a beautiful growth ; are thrifty, clean, free from in- 

 sects of every kind. The theory of soil-poisoning is hard to accept for the reason that 

 every tree is not aftected nd some older trees are not affected — only now and then 

 one with here and there a twig — also the fact that the disease occurs in widely sepa- 

 rated parts of the grove ; and this morning I found one or two young trees in my 

 nursery and some two or three trees in an entirely different part of the 40-acre prop- 

 erty. Chiefly it occurs in places where cow-peas are growing, though the nursery is 

 of course clean, but wherever the disease does occur these bugs are found. The 

 habits of the bug, so far as the orange tree is concerned, are as follows : Usually they 

 are in company, two or more; they rest on the twig, close to it, without motion for a 

 long time. I stood watching six of them this morning for thirty minutes ; they did 

 not move until I disturbed them, but they protruded the termination of the abdomen 

 beyond the wings and ejected with considerable force towards me minute drops of 

 fluid in a continuous spray, an astounding amount of fluid for so small a bug. It wet 

 the leaf that I incloae so that it ran down in a stream to the center and then dried on. 

 I disturbed them, however, and could see no marks of any injury done by them. I 

 found two " Green Soldier Bugs" and two or three " Leaf-legged Bugs," but surely that 

 is nothing to an amount of damage being done. " * * — [C. F. A. Bielby, De Land, 

 Fla., August 1, 1887. 



Reply. — * » * The insect in question is one of the Leaf-hoppers and seems to 

 be a new species of the genus Aiilacizes. Nothing definite can be said as to the work 

 of the insect; that is a point which you will have to determine by observation in 

 your grove. It is quite possible that they do a certain proportion of the damage, in 

 which case the ordinary kerosene emulsion spray, applied for Bark-lice, will doubt- 

 less rid your trees of these also. Certainly the twigs sent by you through the editor of 

 the Florida Dispatch were affected by the so-called " die-back " disease which has been 

 frequently treated in the columns of the Dispatch, and which is mentioned by Mr. 

 Hubbard in his Report on Insects aft'ecting the Orange, and of which you doubtless 

 have a copy. 



Your observation to the effect that the Aulacizes occurs chiefly in places where cow- 

 peas are growing may be an important one. Is the bug found upon the cow-peas 

 also ? The liquid ejected from the bug which you watched is of a saccharine nature, 

 like honey-dew. Allied species are well know to eject this fluid with considerable 

 force. The Proconia, which is foundupon cotton-plants, is remarkable for the distance 

 to which it ejects drops of the liquid. * * * — [August 6, 1887.] 



Second letter. — In accordance with your request for additional specimens of 

 the bug described by you as a new species of the genus Aulacizes I herewith send you 

 tin box containing several of different ages and stages of development. I don't know 

 how many there are in the box, as I caught them this morning with considerable dif- 

 ficulty. 



There was a strong northeast, damp wind blowing,and whether that made them more 

 lively or myself less so I am unable to say ; they are quick in motion, strong in fliirht 

 and very wary. I have discovered the young down to a very minute size, but I can 

 not as yet say as to their eggs, what they are like, or when deposited. I have not seen 

 them on the cow-pea, but my observation leads me to think they are more numerous 

 when this crop is grown in the grove. I judge from the yellow contents of the food- 

 sac that they suck the essential oil from the twig. Would this affect the twig seri- 

 ously ? They choose a position head downward on a twig, not the nearest, but half 

 (or less) hardened. When they are comfortably settled they straighten out the suck 

 ing tube, which, as you know, is short, then with their feet draw themselves downt 

 with one motion, forcing the tube into the twig; they then remain perfectly passive. 

 Whether they eject the fluid when not disturbed or not I can't say ; but when I came 

 near to them, not disturbing them, thej'^ ejected it in my direction ; it is colorless, and 

 leaves, on drying, a whitish deposit on the leaf (I send you herewith two leaves) ; it 



