U) TEKRESTRIAL CARBONIFEROUS ARACHNIDA. 



arc Avoiiderfully well preserved. The tergnm bears many scattered coarse granules, 

 has coarsely <>ranular lateral margins, and a, ])air of coarsely gi-anular longitudinal 

 keels lying slightly obliquely, each keel being rather nearer to the lateral edge than 

 to its fellow of the opposite side ; the sternum, on the other hand, is smooth 

 except for two coarsel}^ granular longitudinal keels, one on each side of the middle 

 line. The sterna in front of this are not sufficiently well preserved for me to state 

 definitely that they were laminate and lobate posteriorly as in Mr. Holt's 

 specimen, but there are indications that this was so. 



Measuremoits in, vnii. — Total length of abdominal portion of opisthosoma 

 (contracted) 28; width of the same (distended) 22; width of tergum of the last 

 segment 17, of sternum 20; length of femur of fourth leg lo, of patella 11, of 

 tibia 11. 



According to Fritsch's restoration, the type of Jsohiitlnis, I. knihipeiisis, Thorell 

 and Lindstrom, resembles Eobnthus ral-ocnlccitsis in the mode of attachment of the 

 coxas of the legs of the third and fourth pairs to the body. It also appears to have 

 the posterior margin of the sterna of the fourth, fifth and sixth segments of the 

 opisthosoma bilobate and mesially notched, as in Mr. Holt's specimen described 

 alcove. On the evidence, therefore, Isohiitltus must be assigned to the same group 

 of Scorpions as Eobathus ; but according to the figures published by Fritsch, 

 Isohutlms has tolerably normal clielas with the movable finger greatly exceeding in 

 length both the length and breadth of the hand. Since the chela3 are unknown in 

 Mr. Holt's specimen, it is possible that the species it represents may be congeneric 

 Avith IsohnUms l-valupensis. 



Genus PALiEOMACHUS, nov. 



1876. Evscorp'uig, H. Woodward (in part), Quart. Joiini. Geol. Soc.,vo]. xxxii, p. 58, pi. viii. 



Generic Characters. — Hand broad and oval, its width greatly exceeding that 

 of the brachinm, its length exceeding that of the fingers, which are short and in 

 contact when closed, the length of the imuiovable digit about equal to the width 

 of the hand. Caudal segments short and stout, apparently about as long as they 

 are wide or high, and not progressively increasing in length from the base to the 

 tip of the tail. 



Ti/pe Species. — Evscurpius aiujliciis, H. Woodward. 



Palseomachus anglicus (H. WoodAvard). Text-figure 2. 



1876. Eoscnrjnus aiujlicnt^, H. Woodward, Quart. Jourii. Geol. Soc, vol. xxxii, p. 58, pi. viii, tig. 3 

 (type), also i gs. 1 and 2. 



The type species of this genus was based upon three specimens, namely, the 

 extremity of a chela from Mansfield in Nottinghamshire, five caudal segments 



