﻿EIGHTH ANNUAL REPORT 



ployment of a patent poisonous compound of the nature of which he 

 is ignorant, when a cheaper one is at hand. The color of the Lodi 

 poison is also very objectionable, as there is much more danger in the 

 use of poisons when their color renders them undistiguishable from 

 ordinary salt. The other powder is one prepared by a gentleman in 

 Philadelphia, and strongly recommended as a ''potato-bug remedy." 

 It was given to me by Dr. J. L. LeConte for trial. It is a dull, yellow- 

 ish powder, which when analyzed proves to be crude "flowers of sul- 

 phur," containing 95 per cent, of sulphur and 5 per cent, of impurity 

 and coloring matter, such as yellow ocher, sand, etc. A thorough 

 trial on the potato patch above mentioned showed it to be entirely 

 worthless. In conclusion, the fact that Paris Green cautiously handled 

 and judiciously used, is an excellent and cheap antidote to the rav- 

 ages of the Colorado potato-beetle, cannot be too strongly urged. 

 That it is useful against some other insect pests is also true ; but it is 

 sometimes recommended for suctorial insects, which it will not affect 

 as it does those which masticate, and its too general use should be op- 

 posed. In an emergency it may be used against the Canker Worm. 

 Yet I cannot recommend it in such a case where other available pre- 

 ventive means are at hand — means which are as simple as they are 

 dangerless. 



A method of using it during the year in suspension that gave sat- 

 isfaction was by pouring a gallon of molasses and a pound of Green 

 into a barrel of water, the molasses having the tendency to make 

 the Green stick better to the foliage. 



THE INSECT'S NATIVE HOME. 



As in the case of all insects that spread or are introduced from 

 one section of country to another, it is interesting to know the origi- 

 nal home or range of the Colorado Potato-beetle, so far as such can be 

 learned, though the question has no especial practical bearing. Fol- 

 lowing Walsh, I have always believed that this species, which has 

 gradually spread to the Atlantic, originally came from the mountain 

 regions of Colorado, and the reasons given are sufficiently convincing 

 to have been very generally accepted as valid. Nevertheless Prof. 

 Cyrus Thomas questions the soundness of the theory in the following 

 language, which I quote because Mr. Thomas's views are entitled to 

 careful consideration : 



The first we hear of its attacking the potato, so far as I can ascertain, is in 1859, 

 at which time it was in Nebraska, about 100 miles west of Omalia ; the next we hear of 

 it is in Iowa, in 18G1, from which point its pro<j:ress has been carefully notetl. Now, it is 

 not contended by any one that it travels except from potato patch to (>otato patch. That 

 it manages in some way to get over intervening spaces of a few miles, is admitted, but 

 never over spaces which require the production of intervening broods. Previous to 



