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DESCRIPTION OF GENERA AND SPECIES. Rie 
what procuryed, almost aligned; the rear row decidedly recurved. The clypeus is compara- 
tively low. The abdomen is a long ovate, in the typical species U. plumipes marked by 
shoulder humps; the dorsum arched, the spinnerets distal, with an additional spinning 
organ known as a cribellum. The legs are in length, 1,4, 2,3, the first leg especially stout, 
and, in all but the two final joints, relatively much more so than the other legs; the apex 
of the tibia is marked in some species by a slight scopula or brushlike cluster of bristles. 
The tibia of leg-IV is provided with a calamistrum in the female. Only one species 
appears to be common in the United States; but one other, U. geniculatus (zosis), has at 
least a lodging place upon the Gulf Coast. The snare of the species is an orbweb, without 
the ordinary viscid armature, for which is substituted the curled threads characteristic of 
Hyptiotes and certain Clubionidee. 
No. 120. Uloborus geniculatus (Oxrver). Plate XXVII, Figs. 1, 2. 
1789. Araneus geniculatus, Ou1ver . . .. Encycl. Method., ii., p. 214. 
1842. Uloborus zosis, WALCKENAER . . Apt. Ins., ii., p. 231, pl. xx., Figs. 1, 2. 
1858. Uloborus Latreillei, Tuorrnn . . Vet. Akad. Forh., xv., p. 197. 
1858. Orithyia Williami, Buackwati. . Ann. Mag. Nat. Hist., 3d ser., iii., p. 331. 
1859. Uloborus domesticus, Dotescuat . Act. Soe. Se. Ind. Neerl., v., p. 46, vii., 2. 
1864. Uloborus borbonicus, Vinson . . Aran. Reunion, etc., p. 258, i, 3. 
1872. Uloborus zosis, Kocu, L. . . . . Arach. Austral., p. 221, pl. xix., 3. 
1873... Uloborus zosis, THoretn ... . Rag. Mal, etc. ii, p. 180. 
1889. Uloborus zosis, Marx. ..... Catalogue, p. 554. 
1889. Uloborus geniculatus, Simon . . . Ann. Soc. Entom. France, p. 131. 
1889. Uloborus zosis, Marx ...... Proceed. Acad. Nat. Sci., Phila., p. 99. 
Fremate: Total length, 7 mm.; cephalothorax, 3 mm. long, 2 mm. wide; abdomen 
5 mm. Jong, 3.6 mm. wide. : 
CrrHaLorHorAx: Cordate, truncated, deeply indented at the base, rounded at the 
margins of the corselet, and nearly as wide in the anterior as in the posterior part; 
corselet well arched, but somewhat flattened on top; fosse a conical pit; corselet grooves 
distinct; cephalic suture well marked; color yellow, with patches of brown on either side 
of the face, and at base of caput; head wide, somewhat quadrate, slightly elevated above 
corselet. Sternum (1b) much longer than wide, of about equal width throughout, except at 
the apex; rounded in the middle; dull yellow, covered with yellowish gray hairs; labium 
about half the length of the maxille, narrow, subtriangular; maxille somewhat longer than 
wide, the tips compressed into an elongated triangle, and directed toward each other; color 
brown at the base, with yellowish tips. 
Eyres: (la.) Ocular quad much wider behind than in front, and the length somewhat 
greater than the rear width; a slight longitudinal cleft separates the midfront eyes, which 
are removed from one another by about a diameter or less; MR somewhat less than MF, 
separated by 1.5 to 2 diameters; side eyes widely separated, the space between them as 
great as that between MR and MF, which is equal to 1.3 the area of MF, or more than 
twice the intervening space; the distance between SR and MR about equals that between 
MR; clypeus somewhat higher than area MF; front eye row procurved, the longer rear row 
slightly recurved. The face is wide in front. 
Leas: 1, 2, 4, 3; femora and tibia stout, but the two apical joints greatly diminished 
in size; color yellow, with broad apical annuli; abundantly covered with gray and brown 
bristles and hairs, and with short, dark spines; the metatarsus of leg-IV is curved, and 
provided on the inner and upper side with a calamistrum (1d). . 
AspomEn: Ovyate, wide and rounded at the base, much narrowed towards the spin- 
nerets, which are distal; color ashen brown or yellow, without any decided folium; the 
epigynum (1c) is without a scapus, and the thick, low atriolum has two short subtriangular 
projections, which are bowl shape or hollowed underneath. 
