DESCRIPTION OF GENEKA AND SPECIES. 161 



No. 18. Epeira ravilla Kocn, C. Plate \, Figs. 7, 8. 



1845. Epeira ravilla, Kocn, C Die Arachnid., xi., p. 73, Fig. 890. 



1889. Epeira rarilla, M.VRX Catalogue, p. 547. 



Fem.\le: Total length, 11 mm.; abdomen, 8 mm. long, 7 wide'; cephalothorax, 5 mm. 

 long, 4 wide; face, 2 mm. wide. General colors, orange yellow and brown for the fore part 

 of the body, and whitish yellow (in alcohol) for abdomen. The specimens here described 

 from Dr. Marx's collection were identified by the late Count Keyserling as Koch's E. ravilla, 

 and after casual examination were drawn and lithographed on the strength of this author- 

 ity along with examples of E. liivariolata Cambridge. Subsequently more careful stmly has 

 satisfied me that there is no specific difference between these and the specimens recognized 

 by Keyserling as E. bivariolata. I regard it as proliable that Koch's E. ravilla and Cam- 

 bridge's E. bivariolata are identit'al, the peculiar blisterliko spots on the lower dorsal field 

 having been overlooked by Kocli, or being wanting in his type, as is the case in some of 

 Dr. Marx's specimens. However, I retain here the names and figures as originally engraved, 

 and append description. 



Cephalothorax : Corselet well rounded on the sides, truncate and indented at the base ; 

 fosse large and circular ; head quadrate, depressed from the gently arched base, covered with 

 gray bristles ; color dull orange yellow with brown marginal hands, the eye space somewhat 

 lighter hue and mandibles dark brown. Sternum orange, slightly longer than wide, sternal 

 cones distinct, elevated in middle, marginal gray bristles ; labium semicircular, maxill.-e 

 gibbous, both dark brown with yellow tips. 



Eyes: Ocular quad elevated, front width greater than rear and equal to length; ilF 

 somewhat larger than MR; separated 1.5 diameter, MR by less than one diameter. Side eyes 

 propinquate, on decided tubercles, SF a little larger than SR ; MF distant from SF about 1.5 

 their alignment, MR from SR by a greater space ; front row recurved, the longer rear row 

 procurved ; height of clypeus about 2.5 diameter MF. 



Legs: 1, 2, 4, 3 ; stout, especially I, II; orange yellow; femoi'a-I, II, almost entirely 

 dark brown to blackish, and about half of femur-IV similarly marked ; joints annulated ; 

 well armed with white and yellowish spines and gray bristles and hairs ; palps of lighter 

 hue, with bright yellow wings and strong gray bristles. 



Abdomex : Oval, contracted both in front and behind; dorsum lightly arched on top, 

 rounding thence to the spinnerets directly beneath the high apical wall. The dorsal pat- 

 tern. Fig. 7, and on the anterior base, is a rhomboidal patch of wdiitish yellow color, the 

 original hue of which may have been green or bright yellow ; smface with stout white 

 bristles, with raised brown sockets. In the median line on the lower part of the dorsal 

 saddle are two circular blisterlike markings like those in E. bivariolata, separated about two 

 mm., the lower one smaller than the upper. The sides are yellow, with lateral streakings 

 of dark color. The venter has a chapeau shaped spot of brown surrounded with yellow ; 

 at the orange colored spinnerets and along the sides bordered l)y brown. The epigynum, 

 Fig. 7a, in the specimen described, probably lacks one moult of maturity ; scapus moder- 

 ately long and pointed. 



Male : Fig. 8 ; resembles the female in color and pattern ; length, 8 mm. ; cephalo- 

 thorax longer and wider relatively than in the female ; fosse a longitudinal depression. 

 The legs have less prominent bands of black on the femora and are strongly annulated 

 throughout; tibia-II much swollen and curved, and armed with stout, brown clasping 

 spines arranged in two rows on the side, and one underneath ; ordinary spines whitish, 

 with brown bases ; metatarsus curved, thin, one stout brown spine on the inside near the 

 base, two near the apex ; patellar joints long and rather thin ; a long brown spur on apex 

 of coxa-I ; the palpal digit is remarkably developed (Fig. 8a), the corneous processes resem- 

 bling those of E. bivariolata. The abdomen clothed at the liase with a cluster of long gray 

 bristles; circular blisters on the dorsal apex as in female. 



Distribution : Texas ; a male from El Paso, Isleta, Rio Grande. (Marx Collection.) Dr. 

 Marx also locates it in Arizona. It is probably an inhabitant of the entire Pacific Coast, or 

 at least the tropical or semitropical sections. Koch's E. I'avilla was from Mexico. 



