ACADEMY OF NATUKAL SCIENCES. 9 



and honey produced by the labor bees, are familiar to all. The 

 gall-nut, which forms the basis of one of the most valuable 

 articles known, I mean ink, is due to the labors of an insect on 

 a variety of oak. Gum ammoniac, the varieties of lac (shell-lac, 

 lac-lake, and stick-lac), have a similar origin. To various species 

 of coccus we are indebted for several important dyes, among the 

 most conspicuous of which is the cochineal. The varieties of 

 cantharides afford blistering materials ; and a tea made of bees 

 has been recently found useful in a distressing disease.* 



Within a short time, the unexpected presence of microscopic 

 insects in certain regions has been supposed to show the course of 

 the winds ; when their habits and geographical distribution are 

 fully ascertained, their appearance in any unusual locality may 

 be relied upon as an indication of the direction of atmospheric 

 currents. 



A class of animals which exercises an influence of such extent, 

 for good as well as for evil, over the condition of man, is surely 

 worthy of his attentive study. 



Conchologists have described about 15,000 species of mollusks. 

 They afford food to man and other animals. The strata of the 

 earth records their antediluvian existence ; hence a knowledge of 

 conchology enables the geologist to recognize fossil shells, the 

 presence of which serve to characterize certain formations. 



Herpetologists have made us [acquainted with about 2,000 

 species of reptiles, and established the means of distinguishing 

 those which are harmless and useful from those which are poison- 

 ous and fatal. 



Naturalists have described about 10,000 species of fishes, a 

 class of animals from which man derives almost incalculable 

 benefits. To be convinced of the truth of this assertion, it is 

 only necessary to glance at the extent and value of the various 

 fisheries in the world. 



About 6,000 species^ of birds have been described. _ The value 

 of the study of ornithology has been so beautifully stated by one 

 of the earliest members of the Academy, that I will quote his 

 language. Alexander Wilson, in the preface to the fifth volume 

 of his "American Ornithology" says : 



" In treating of those birds more generally known, I have 

 endeavored to do impartial justice to their respective characters. 



* Dunglison on New Remedies, p. 703. Philadelphia, 1851. 



