On JS'orth American Spiders. 109 



Pickering of Philadelphia, to whom I am much indebted ; but, when 

 stuck through with a pin, and dried as other insects, these become so 

 shriveled as to make it sometimes impossible to recognize them, and 

 always so to describe new species.^ Spiders should be preserved in 

 diluted alcohol, or brandy, in which they preserve their form, though 

 their colors are usually impaired in it. 



The number of 125 species will appear very large, but I could 

 have swelled the list to 1 50. Spiders differ from true insects, or at 

 \east ivinged Insects, m ihe'ir growing. They come out from their 

 eggs very minute, and continue to increase in size, probably for sev- 

 eral years in many species; whereas, with few exceptions, insects 

 come out of their pupa state, at once, with the size which is peculiar 

 to them. The ARANtiDES, in their different ages, present differences 

 of color and marking. The seasons also produce a change in the 

 colors of some spiders ; and, I am nearly convinced that the first frosts 

 produce a total change in the dress of several described Epeir^ 

 which may be referred to one name. These are the considerations 

 which have induced me to be very cautious in adopting new species, 

 and comparing many specimens in different seasons, when possible, 

 before I described them. 



APPENDIX. EDITOR. 



Juvenile Observations of President Edioards on Spiders. 



Ever since the following article on spiders,' appeared in the late* 

 edition of the works of President Edwards, with a memoir of his 

 life, I have intended to republish the following extract, and it seems 

 to follow naturally in the train of the learned monograph of Professor 

 Hentz. Without pretending at present, to discuss the merits of the 

 theory of Edwards, the observations recorded by him present a 

 very curious and interesting proof of philosophic attention, in a 

 hoy of twelve years, and evince, that the rudiments of his great 

 mind were, even at that immature age, more than beginning to be 

 developed. The first volume of his works, contains many other very 

 curious and interesting speculations and observations on different sub- 

 jects of physical science ; on meteorology — on electricity — on crys- 

 tallization — on geology — on chemistry — on an atomic theory, &:c. 

 They present indubitable evidence of that acuteness, vigor, precision 

 and penetrating sagacity, which, had he devoted himself to physical 



* 1829— S. Converse, New York, 10 Y»ls, 8vo. 



