274 AMERICAN SPIDEKS AND THEIR SPINNINGWORK. 



Male: 5 mm. long; in color and form resembling the female. The ceplialothorax 

 is roundly oval, the summit of the corselet has two dark, brown bands, which run along 

 the cephalic suture ; on the sides are irregular bands of yellow, bordered beneath by brown, 

 and the margin of the corselet is yellow ; skin with gray pubescence. The ocular quad is 

 longer than wide, the rear wider than the front ; MF are slightly larger tlian MR, the latter 

 about equal in size to SR. The eyes of the rear row are nearly equally divided one from 

 another, MR being slightly further apart. Of the front row the space between SF and MF 

 is about one-half greater than the distance between IMF. SF are quite small, the smallest 

 eyes of the entire group. The first row of eyes is procurved ; the rear row is slightly 

 recurved. The palps are sliort ; the digital bulb large, globular ; the cymbium covered 

 thickly with strong, yellowish hairs. The legs are yellow, with dark brown apical and 

 median annuli ; length, 1, 4, 3, 2, the first pair much longer and stouter. The tibiae of 

 leg-I are slightly curved, thickened towards the apex, upon the summit and sides of which 

 are rows of strong, black spines; the other legs are armed with short, black spines; as in 

 the female, the two terminal joints are decidedly thinner than the others. 



DisTKiBUTiON : The Gulf Coast of the United States and the West Indies. 



No. 121. Uloborus plumipes (?) Lucas. Plate XXVII, Figs. 4, 5 ; XXVIII, Fig. G. 



1842. Uloborus Americanus, Walcken'e* Ins. Apt., ii., p. 229 ; Abbot, G. S., No. 44, 45. 

 1845. Vloborus plumipes, Lucas .... Explor. de I'Algerie, Anim. Artie, i., 252; pi. 15, 



Fig. 8. 

 1850. Pldlhjra mammeata, Hentz* . . . B. J. S,, vi., 25 ; Sp. U. S., 129, pi. 14, Fig. 16. 



1850. Ph'dlyra riparia, Hentz Ibid., v., Fig. 17. 



1869. Uloborus plumipes, Canestrini & 



Pavesi Archiv. p. la Zool. I'Auat. e la FisioL, ser. ii., vol. ii. 



1881. Vloborus villosus, BLeyserling* . N. Spinn. a. Amer., iii., Verh. Ges. Wien, 278, xi., 0. 



1888. Uloborus plumipes, Emerton . . N. E. Ep., Ciniflon., Trans. Conn. Acad., pi. xi., 1. 



1889. Uloborus plumipes, IMcCooK . . . Amer. Spiders and their Spinningwork, I., II. 



Dr. Marx, in his Catalogue, considers Uloborus Americanus as a good species and identical 

 with U. mammeata (Hentz). The figure in Abbot's MSS. drawings, from which Walckenaer 

 described his species, certainly resembles in outline Hentz's drawing of U. (Phillyra) 

 mammeata rather than his figure of U. riparia (plumipes) ; but the front row of eyes is 

 moi-e decidedly procurved. I am inclined to think that the two species are the same, and 

 are identical with U. plumipes Lucas. If so, Walckenaer's name should have priority. 

 Not having suflicient material to determine the point positively, I leave the name as above, 

 and place in the synonyma marked (*) the series corresponding most closely with U. 

 Americanus, as distinguished by Marx and Hentz. I believe, however, that it will prove 

 that we have but one species under the various names as above, and that the confusion in 

 names has been caused by the striking difi'erence in appearance between the black forms 

 and the yellow ones, as fairly represented upon the figures in my plates. Perhaps it may 

 be concluded that these differences justify at least varietal names. 



Female: Total length, 5 mm.; cex)halothorax, 2 mm. long, 1.3 mm. wide; abdomen, 

 3.5 mm. long, 1.75 mm. wide. 



Cephalothorax : Oval, truncated at the base, the sides rounding with nearly equal 

 width to the face; corselet high behind, where it is raised into two low humps by the 

 parting of the median fosse, thence it slopes rather sharply to the base; the head elevated; 

 color blackish brown, covered with yellowish pubescence. Sternum (4a) cordate, inclined 

 to oval, longer than wide, of nearly equal width throughout except at the apex, elevated 

 in the centre; color blackish brown, with gray pubescence. Labium about half the height 

 of maxillte, width about equal to length, the tip triangular; maxillse squarish, longer than 

 wide, truncate at the tips ; color of both labium and maxillae yellow. 



Eyes: Ocular quad elevated in front, much wider behind than in front, and length 

 greater than width ; MF smaller than IMR, and divided by about one diameter, MR by two 



