80 TERRESTRIAL CARBONIFEROUS ARACHNIDA. 



In front of the eje-l)earing elevated portion tliere is a sliglitly lower anterior 

 projection, abont equal to it in width, the sides of which diverge posteriorly and are 

 continuous with the Intei-al edge of the carapace; the summit of this projection is 

 compressed to form a median crest with sinuous edges. The lateral portions of 

 the carapace are depressed, somewhat widely extended beyond the elevated 

 median area and marked with four grooves, the anterior of which is nearly 

 longitudinal and lies alongside the anterior median projection ; the following two 

 are oblique, the first of them joining at its posterior end the transverse sulcus of 

 the elevated area. The posterior groove is transverse and nearly in a line with the 

 posterior border of the elevated area; it defines laterally the posterior part of the 

 carapace, which is a short, wide area lying behind the median elevated portion ; 

 the posterior border of this, which abuts against the opisthosoma, is straight. The 

 posterior angles of the carapace are rectangular, and the lateral margins slightly 

 convex but becoming more strongly so anteriorly, where they curve inwards and 

 forwards to meet the lateral margins of the anterior projecting portion ; where the 

 three posterior grooves reach the lateral margin they form angular projections 

 making the lateral margin irregular in outline. 



The opisthosoma shows only seven tergal plates ; its anterior border where it 

 abuts against the prosoma is straight; its sides are convex; at its widest it is as 

 wide as the prosoma, and is narrowed and oval behind. The posterior border 

 of all the tergal plates is straight and transverse, except of the last. Each 

 plate is marked on each side by a sulcus separating a pair of lateral laminte from 

 the wider median portion of the tergum ; these lateral plates are four-sided, with 

 the exception of those of the seventh segment, Avhich are triangular. 



'I'ljpe Species. — Aphantomartns areolatus, sp. nov. 



Although obviously related to Eoplivynus and Krelscheria , judging from the 

 shape and segmentation of the carapace, this new genus decidedly differs from 

 both not only in the structural details of that plate but also in those of the 

 opisthosoma. For example, there is no sign of any segment or segments in front 

 of the seventh from the end, and the posterior l)order of all the tergal plates is 

 straight from side to side instead of ])resenting a strong recurvature at least in the 

 posterior part of the body. The opisthosoma of Apliantomartas, indeed, differs very 

 markedly from that of all the described genera of Eophrynidse, especially at its 

 ])Osterior extremity. Some of it may possibly be buried in the matrix or missing, 

 but the appearance of the fossil does not bear out this suggestion, the plausibility 

 of Avhich is further lessened l)y the occurrence of the same features in three 

 specimens. 



It is also possible that the peculiarities in the structure of the opisthosoma are 

 due to immaturity, a possibility supported in a measure by the small size of the 

 specimens as compared with the types of Kreischcrla verrucosa and of Eophri/nus 

 prestcici. But although the possibility that the pleural laminse increase in size 



