14 



ered, and such subgenera as were not known to those authors, 

 without materially altering their superstructure. But when 

 the work is accomplished, and all nature is described by man, 

 the number of species included in the common word spider will 

 be truly amazing. Walckenaer enumerated two hundred and 

 sixty species thirty-four years ago, and Latreille could easily 

 have doubled the catalogue, if the number of species had been 

 mentioned in the last edition of the Regne Animal. The 

 writer of this- paper, in the course of twenty years, has, at 

 stolen hours, collected and described one hundred and forty- 

 seven species ; but he is convinced that fifty more could be 

 added ; as he has not explored the vast peninsula of Florida, 

 nor any portion of Louisiana. Two hundred species, therefore, 

 would be a low estimate of the number of spiders inhabiting 

 the United States, not including the territories yet unoccupied 

 by civilized men. It is obvious that the number of species 

 throughout the world will amount to more than two thousand, 

 when the natural history of all countries is complete. It is 

 equally obvious that the rapidly increasing number of new spe- 

 cies requires subdivisions, when it is practicable to make them. 

 The subgenus now proposed is indispensable, as the species 

 cannot be classed under any existing generic name. It will be 

 placed in a natural order immediately after Pholcus. 



Subgenus Spermophora. 



Eyes, six, in two clusters, one on each side of the cephalo- 

 thorax, PL 17, fig. 9. 



Legs, the first pair longest, then the fourth and second, nearly 

 equal, the third pair shortest. Length moderate, slender. 



Lip, wide, triangular. 



Maxilla, tapering towards the point, inclined over the lip. 



Mandibular, short, conical, with very small fangs. 



The characters derived from the tropin are nearly those of 

 Pholcus, but the absence of the two eyes in front of the 



