April, ’24] 
SCIENTIFIC NOTES 
343 
Scientific Notes 
Blister Beetle—Serious Pests in Northern Arizona. .Serious infestations of 
blister beetles during the past two years have made potato raising an uncertain 
problem in Chino Valley and on farms near Prescott. This being a comparatively 
new farming region and a tract of ground only recently opened up, it is evident that 
the beetles are migrating from the native vegetation. As two of the beetles have 
not heretofor been reported from Arizona, the following notations are of interest. 
Macrobasis longicollis Lee.-—-On July 18 ,. 1922 in Chino Valley these insects were 
found traveling in swarms and completely defoliating small potato fields. There 
were considerable areas where even the stems were cut to within four inches of the 
ground. By August 10 , 1922 the swarms had scattered and the beetles could only be 
seen here and there on fields that had escaped the earlier infestation. In the summer 
of 1923 they again appeared in numbers. 
Epicauta corvina Lee,—Approximately a month after the visitation of Macrobasis 
longicollis, this species put in its appearance in the same locality. These did not 
travel in swarms but could be seen running in all directions over the fields, along the 
ditch banks and across roads. They did not concentrate on the potato fields alone 
since their native food, the puncture plant ( Tribulus terrestris ), was growing abundant¬ 
ly on the waste ground and along the road sides. The insects were feeding on the 
potato plants and the weeds in about equal numbers. 
Epicauta pardola Lee.—In June 1922 these blister beetles were found in great 
swarms feeding on alfalfa and potatoes in Skull Valle}*. The beetles were so num¬ 
erous that from a little distance the alfalfa appeared blue as though it were in full 
blossom. In some instances as many as fifty beetles could be found on a single 
plant. They feed on the most tender leaves and buds, necessitating an early cutting 
of the crop. 
In general the spraying with arsenate of lead has been done after the insects began 
their attack and this is generally too late in the case of Macrobasis longicollis, as 
the insects are capable of defoliating large areas in a few hours. The spray applied 
at the first appearance of the beetles killed large numbers, but not before evident 
damage had been done. In the case of Epicauta corvina it was used with a greater 
degree of success. 
Harold R. Brisley, Plant Pathologist, United Verde Extension 
Mining Co., Clemenceau, Arizona 
Toxicity of Sodium Fluoride to Man. The growing use in the home of sodium 
fluoride against roaches and as a repellent for ants emphasizes the need of definite 
knowledge of its toxicological principles. Sollman’s “Pharmacology” states that 
“Fluorides have a very strong local irritant action. Their systemic action re¬ 
sembles that of oxalic acid and is probably produced in the same manner by the 
formation of insoluble calcium salts.” In a recent paper (Jour, of Pharmacology 
and Experimental Theropeutics, vol. 17 (1921), p. 197) the same author states that 
“Small doses of soluble fluorin preparations, even to one miligram per kilogram 
(0.06 of a gram for a 160-pound man) of weight are toxic and should be absent from 
the food of man and animals.” The symptoms of poisoning from the fluoride iron 
are muscular weakness, difficulty of breathing, low blood pressure and inflammation 
of the entire alimentary canal.” 
