ir>r, THE AMERICAN MONTHLY [July, 



San Francisco, Cal. — Wm. E. Loy, Sec'y. 



May 28^ i8go. — Dr. Montgomery exhibited the eggs ot a minute 

 insect, the Chigger {Leptus irritatis) . This is a parasite afflicting the 

 human race, chiefly met with in the Mississippi Valley, and its pres 

 ence causes great suffering to its host. In its habitat it is variously 

 known as " chigger," " jigger," " red bug," and " hai-\^est bug." It 

 makes its appearance in tlie early summer, about the ist of June, and 

 continues to annoy human beings until the first frost of the season kills 

 it ort'. The pests are most active in August, and are found on all kinds 

 of vegetation, but especially on blackberry bushes. They are not 

 likely to be found on cultivated vegetation, and do not thrive well in 

 wet seasons. They attach themselves to the clothing, and immediately 

 seek a suitable spot on the subject to begin operations. So far as known 

 they do not infest any other animal. The female penetrates the skin 

 and within a few hours completely buries itself. The body then begins 

 to swell from the formation of eggs, and increases to five times its size. 

 This causes irritation and swelling, accompanied by intense itching. 



In Virginia the negroes remove the intruder with the point of a red- 

 hot iron, and then poultice the wound with the universal panacea of 

 the race — a fresh quid of tobacco. 



Mr. Riedy and other members gave an exhibition of beautifully 

 arranged slides, prepared by E. Thum, Leipzig. These consisted 

 chiefly of beautiful diatom frustules, arranged in the form of rosettes, 

 or interspersed with butterfly scales, and were shown with transmitted 

 light and dark-field illumination. There was, also, shown a series of 

 opaque objects, consisting chiefly of variously colored butterfly scales 

 arranged in the form of vases with a bouquet of flowers, and hovering 

 around the flowers a number of bees or humming-birds. When it is 

 considered that these elaborate designs in their entirety are not dis- 

 tinguishable to the naked eye, and that from 100 to 500 separate bits 

 of butterfly scales or diatoms enter into their composition, they are 

 simply marvellous works of human handicraft. Another slide of a simi- 

 lar nature consisted of 100 distinct species of diatoms arranged in 

 rows, and an accompanying catalogue gives the specific name of each. 

 When viewed under the miscroscope these various preparations exhibit 

 great brilliancy of coloring and perfection of arrangement. 



Jjifie 4, i8go. — The meeting of the .Society, held at 120 Sutter street, 

 was a very important one, being the twentieth anniversary of its organ- 

 ization. An historical address was read by Henry G. Hanks. The 

 reunion was one of general interest to those present, and of special in- 

 terest to the few original founders who were able to attend. 



The reading of the address occupied about one hour, and contained 

 a brief sketch of the founding and development of the society. Those 

 jiresent were then invited to partake of refreshments, Colonel C. Mason 

 Kinne presided and announced the following: 



''Our Founders," response by Colonel C. Mason Kinne. 



" Our Life Members," response by Jacob Z. Davis. 



" Our Honorary Members," response by Professor George Davidson. 



*' Our Presidents," response by Dr. S. W. Dennis. 



'' Our .Secretaries," response by Dr. C. P. Bates. 



" Our Workers," response by Dr. J. H. Stallard. 



" The Press," response by Professor E. J. Wickson. 



