GENERAL CLASSIFICATION' AND STRUCT1KK. 



17 



The following tabular exhibit is given of this classification, or group- 

 ing, if that word seems to any one more suitable : 



CLASS AKACHXIDA. 



ORDER ARANE.E. 



I. First Division. Sedentary Spiders. 



Tribe 1. Orbitelaria?, 1 Orb weavers. 

 " 2. Retitelarise, 2 Lineweavers. 



Tribe 3. Tubitelarise, Tubeweavers. 

 " 4. Territelaria?, Tunnelweavers. 



Black- 

 wall's 

 Classifi- 

 cation. 



II. Second Division. Wandering Spiders. 



Tribe 5. Citigradse, 3 Citigrades. Tribe 6. Laterigradse, Laterigrades. 



Tribe 7. Saltigrada?, Saltigrades. 



This arrangement is the best, perhaps, that can be adopted, and seems 

 more natural and satisfactory than that which commanded the approval of 



such a distinguished arachnologist as 

 Blackwall, and which is based upon 

 the number of the eyes. Blackwall 

 founded three tribes, within which all 

 the species known to him are includ- 

 ed. They are: (1) Octonoculina, eyes, eight ; (2) 

 Senoculiiia, eyes, six ; (3) Binoculina, eyes, two. 

 In the first tribe, Octouoculina, which is the 

 most extensive of the three, he included all the 

 genera having eight eyes, without regard to 

 other characteristics or to the considerable dif- 

 ferences in organization and economy. The 

 second tribe, Senoculiiia, as known to Black- 

 wall included but ten or eleven genera, and 

 embraced all tribes having six eyes, with the same disregard to other char- 

 acteristics. The third tribe, Binoculina, contained the single genus Xups. 

 instituted by Mr. \V. S. McLeay for the reception of two remarkable sj 

 of extra European spiders. 4 The Latreilliaii classification, which Thorell 



1 Aranete Orbitelaripe : Perty, Delect. Anim. Art. Bras., page 193. 



- From rotas, a net. The word " net" very well expresses the knotted and meshed char- 

 acter of most spinningwork of this group. But since it is used popularly as a general term 

 for the webs of all spiders. I have preferred "Lineweavers" to " Xetweaven? " as a dis- 

 tinctive popular name of this tribe. 



3 Prof. Thorell assigns the Laterigrades to the fifth tribe, the Citigrades to the sixth. I 

 have ventured to so far change this arrangement as to reverse the positions of the Lateri- 

 grades and Citigrades. The Citigrades appear to me to approach the Tunnelweavers and 

 Tubeweavers, both in structure and economy, more nearly than the Laterigrades. So also 

 the step from the Citigrades to the Laterigrades through the genus Dolomedes appears more 

 natural than the reverse, as Thorell has it : and the step to the Saltigrades from the Lateri- 

 grades is quite as, if not more, natural than from the Citigrades. From the standpoint of 

 economy alone the passage is certainly easier. 



4 Blackwall. "Spiders of Great Britain and Ireland," Preface, page 6. 



FIG. 3. Laterigrade Spider, Misume- 

 na rosea Keyserling. 



