The spiders of the northern states

"The particular difference between the lower animals are generally but little observed. It is, therefore, well, as introductory to the study of a certain set of animals, to observe the place they occupy in the systematic arrangement of Natural History. This draws the attention of the student to their peculiarities, and, at the same time acquaints him with all related and resembling family." *- From the introduction to the 1901 edition.*