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On a New and Interesting Spider. 



By Geo. IVIarx, M. D. 

 Washington, D. C. 



The family P/io/ddce has been hitherto placed in close relation with 

 the TheridiidcB, but the peculiar structural characters of this small but 

 well marked family have made this affinity doubtful to some of our 

 systematists. In fact, the right place for the Pholcidce has not been 

 found so far, and all our modern arachnologists content themselves 

 with leaving it where it was, near the Theridiidce. Duges alone placed 

 it with Fih'siata, but for what reason I do not know. 



In July last I received, from the vicinity of Lookout ^Mountain, 

 Tenn., a few males and females of a spider, which were collected in 

 the forests of that mountainous region, where they had constructed, at 

 the underside of projecting cliffs and rocks, large, white, saucer- or 

 lampshade-like webs, in which they dwelt, assuming an inverted posi- 

 tion, and shaking the web like a Pholciis, when one approaches. 



This spider appeared at the first glance to be a Pholcus from its 

 long, slender legs, the shape of the body and the arrangement of the 

 eyes ; but a closer study showed that it was an entirely new animal, 

 with characters widely differing from any known spider, and yet com- 

 bining in itself some of those characters upon which a certain number 

 of families form a natural group, viz : Dysderidce, Filistatida: and the 

 Territelarice. Moreover, this spider brings into this group the Pholcidce 

 and ScytodidcR, since it possesses characters which belong to these 

 families. 



The principal and peculiar characters of this interesting spider are 

 as follows : // has four true lamellar trachete or lungs like the Terrifel- 

 arice. It has a cribellum and calamistrum like the Fillslaiidte. It has 

 the nearly vertical mandibular claws and the male palpus, like the 

 Dysderidce. It has the legs and body shape and the arrangement of the 

 eyes of the Pholcidce. 



But it is unlike the hitherto known Territelarice in the presence of 

 a cribellum and calamistrum, in the slenderness of the legs and in the 

 shape of the body. It is unlike the Filistaiidce from its four lungs, the 

 position of the mandibular claws and the form of the labium. It is un- 

 like the Dysderida; from the number of the eyes, the presence of the 

 cribellum and calamistrum and the length of the tarsi. It is unlike the 

 Pholcidce by the presence of four lungs, the cribellum and calamistrum 

 and the direction of the mandibular claws. 



The fact that our spider has four lungs places it at once in the 



