18 AMERICAN SPIDERS AND TIIICIK SPINNINGWORK. 



lias so adiiiii-alily expressed as above, will at k'ast be preferred by those 



who set as iiiucli store upon tlie haliits and functions of the creatures as 



upon their forms. The latter indeed will not be undervalued by a wise 



and careful student ; but tlie systeiiiatists and anatomists Avill doubtless 



bear with those who would fain keep natural history from swinging too 



far away from the paths which earlier naturalists trod, and which so 



thoroughly traversed the life history of created things. 



A general classification based upon the spider's behavior, especially in 



relation to its chief function, has the advantage that it compels attention 



to the creature's habit without at all neglecting its structure. It 



The Clas- i^ not claimed that this classification is without obiections. There 

 siflcation -11 • -i- 1 • 1 • 1 -11 



Justified '^'"'^' i"'''-^'^''' some nicongruities, more or less serious, whicli wnl 



appear hereafter. But until these interesting animals shall have 

 received from naturalists that attention which their character and impor- 

 tance in nature ju.stify, and which will enable some future arachnologist to 

 show us a better way, we shall, perhajjjs, be best repaid by accepting tliis 

 general grouping of the great families of the spider fauna. At least it is 

 that which best serves my own purposes in the special lines marked out 

 for this treatise. 



Students who are interested in a more thorough consideration of this 

 point will find the objections to the above system well stated, and a classi- 

 fication proposed based more upon anatomical structure, by Dr. Philip 

 13ertkau, of Bonn.' A very satisfactory answer to these objections has 

 been published by Prof. Tamarlan Thorell, M. D.,^ who adheres substan- 

 tially to his former system but, confessing his indel)tedness to Prof. Bert- 

 kau for certain modifications, proposes a rearrangement whicli, he thinks, 

 answers to our present knowledge of this order, as follows :■•- 



Ordo Arane.e. 



SUBORDO I. TeTRAPNEUMONES. 



Tribus I. Territelariaj. 



SuBORDO II. DiPNEUMONES. 



Tribus II. TuliitelaricTj. 

 Ecribellatie. Cribellatae. 



Tribus III. Retitelarise. 

 Tribus IV. Orbitelaria'. 

 Cribellatie. Ecribellatie. 



Tril)us V. LaterigradtE. Tribus VI. Citigradse. Tribus A'^II. Saltigradse. 

 The scheme embraces Euroi)eaii families for the most part, Init includes 

 a few exotic ones. 



•See especially his "Vereuch einer natiirlichen Anordnung der Spinnen," in Archiv fiir 

 Naturgescbichtc, xliv., i., page 3.51, sq., 1878; and his treatise " Ueber das Cribellum und Cala- 

 niistnim. Ein Beitrag zur Histiologic, Biologic, nnd Sy.^tcmatik der Spinnen," ibid., xlviii., i. 

 page 810, etseq., 1882. 



^Annals and Magazine Nat. Hist., Apt., 1880. "On l>r. I'cvtkan's (.'las.silication of tlic 

 Order Araneie or Spidere," by Prof. T. Thorell. 



