18 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



has SO admirably expressed as above, will at least be preferred by those 



who set as much store upon the habits and functions of the creatures as 



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



and careful student; but the systematists and anatomists will 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- jg ^^^ claimed that this classification is without objections. There 



T o.-^ J are, indeed, some incongruities, more or less serious, which will 

 Justified. ' ' . . 



appear hereafter. But until these interesting animals shall have 



received from naturalists that attention which their character and impor- 

 tance in nature justify, and which will enable some future arachnologist to 

 show us a better way, we shall, perhaps, be best repaid by accepting this 

 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 w^ho 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 

 Bertkau, of Bonn.^ A very satisfactory answer to these objections has 

 been [>u])lished by Prof. Tamarlan Thorell, M. D.,^ who adheres substan- 

 tially to his former system but, confessing his indebtedness to Prof. Bert- 

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

 answers to our present knowledge of this order, as follows : — 



Ordo AraneyE. 



SUBORDO I. TeTRAPNEUMONES. 



Tribus I. Territelarias. 



SuBORDO II. DiPNEUMONES. 



Tribus II. Tubitelarite. 

 Ecribellata). Cribellatse. 



Tribus III. Retitelaria3. 

 Tribus IV. Orbitelarise. 

 Cribellatffi. Ecribellatte. 



Tribus V. Laterigrada3. Tribus VI. Citigrada). Tribus VII. Saltigradae. 



Tlie scheme embraces European families for the most part, but includes 

 a few exotic ones. 



'See especially his "Versuch einer naturlichen Anordnung tier Spinnen," in Archiv fiir 

 NuturgeHclii(-hte, xliv., i., i)ago .351, sq., 1878; and his treatise "Ueber das Cribellum iind Cala- 

 niiHtruiii. Ein Beitrag zur Ilistiologio, Hi()lo<-ie, nnd Systcmntik (l(>r Spinnen," iltid., xlviii., i. 

 page 81(1, et sofi., 1882. 



'^Annals an<i Magazine Nat. Hist., .\pl., lS8(i. "On Dr. I'.crtkairs ('lassifK-ation of the 

 Order Aranea; or Sjiidcrs," l)y Prof. T. Tliori'U. 



