570 



ARACHNIDA. 



[ANT. EOS. 



more or less wedge-shaped, and visible above as well as below, the arrangement of 

 which corresponds to that of the coxse. The abdomen forms a single mass, and is 

 composed of a variable number of visible segments, ranging from four to nine. 

 Palpi not much longer than the legs, simply terminated. 



ORDER ANTHRACOMARTI. 



FAMILY ARCHITARBID.E. Anthracomartus, Architarbus, Geraphrynus. 

 FAMILY ARTHROLYCOSID^:. Arthrolycosa. 

 FAMILY POLIOCHERIDJE. Poliochera. 



ORDER PEDIPALPI. 

 FAMILY GERALINURID^E. Geralinura. 



ORDER SCORPIONES. 

 FAMILY EOSCORPIONID.E. Eoscorpius, Mazonia. 



ANTHRACOMARTUS, Karsch, 1882, Zeitschr. 

 deutsch. geol. Gesellsch., p. 556. [Ety. 

 anthrax, coal ; Martos, proper name.] 

 Cephalothorax quadrate, the front 

 square or scarcely convex, about half 

 the size of the abdomen ; coxae radiat- 

 ing from a broad triangular sternal 

 plate, the base of which forms the 

 posterior margin ; sides of body con- 

 stricted so as to show a distinct 

 though slight separation of cephalo- 

 thorax and abdomen ; abdomen orbic- 

 ular, composed of seven segments of 

 similar length throughout. Type A. 

 volkelianus. 



pustulatus, Scudder, 1884, Proc. Am. 

 Acad. Arts and Sci., p. 13, Low. Coal 

 Meas. 

 trilobitus, Scudder, 1884, Proc. Am. Acad. 



Arts and Sci., p. 13, Coal Meas. 

 AKCHITARBUS, Scudder, 1868, Geo. Sur. 111., 

 vol. 3, p. 568. [Ety.-archaios, ancient; 

 tarbos, object of alarm.] Cephalothorax 

 orbicular, broadly rounded in front, 

 much smaller than the 

 abdomen, but not sepa- 

 rated from it by a marked 

 lateral constriction ; coxae 

 radiating from a central 

 pit ; abdomen oval, com- 

 posed of nine segments, 

 of which those on the 

 basal half are very much 

 shorter than the others, 

 and on the dorsal sur- 

 face are forced still more 

 closely together by the 

 large post-thoracic plate ; 

 no abdominal append- 

 ages. Type A. rotundatus. 

 rotundatus, Scudder, 1868, Geo. Sur. 111., 

 vol. 3, p. 568, Coal. Meas. 



FIG. 1064. Ar- 

 chitarbus ro- 

 tundatus. 



ap- 



ARTHROLYCOSA, Harger, 1874, Am. Jour. 

 Sci. and Arts, 3d ser., vol. 7, p. 219. 

 [Ety. arthron, a joint ; 

 lykos, a spider.] 

 Cephalothorax orbic- 

 ular, twice as large 

 as the abdomen ; 

 Coxee radiating from 

 a central pit; ab- 

 domen oval much 

 narrower at the base 

 than the cephalo- 

 thorax, with no Ion- 

 gitudinal sculptur- 

 ing, and composed 

 of seven segments ; no abdominal 

 pendages. Type A. antiqua. 

 antiqua, Harger, 1874, Am. Jour. Sci. 

 and Arts, 3d ser., vol. 7, p. 219, Coal 

 Meas. 



EOSCORPIUS, Meek & Worthen, 1868, Am. 

 Jour. Sci and Arts, 2d. ser., vol. 46, p. 

 25, and Geo. Sur. 111., vol 3, p. 560. 

 [Ety. eos, dawn; scorpiils, a scorpion.] 

 Cephalothorax quadrangular, some- 

 what wider behind than long ; mesial 

 and lateral furrows between which the 

 surface bears granules; mandibles 

 stout, without teeth or serrations ; mov- 

 able finger curved and sharp at the point ; 

 legs stout, divisions long ; abdomen 

 twice as long as as Cephalothorax ; 

 segments gradually increase in size to 

 the sixth, while the seventh and last 

 is 2J times as long as the sixth, but 

 rapidly contracts, and is truncated for 

 the attachment of the tail ; the anterior 

 margin of each of the first six segments 

 is rounded ; the three tail, segments 

 preserved are stout, oblong, and covered 

 with granules; the comb-like organ 

 shows 11 or 12 divisions. Type E. 

 carbonarius. 



