APHANTOMARTUS. 



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with growth must be borne in mind, there is as yet no evidence of the fact ; and 

 even were it known to be the case, the species now under discussion could not 

 be assigned either to Eophrynus or Kreischeria, on account of the structure of the 

 cai-apace and the sculpturing of the opisthosoma. 



Aphantomartus areolatus, sp. nov. Plate III, fig. 6; Text-figure 41. 



Carapace wider than long, its median area with areolate sculpturing of large, 

 low, contiguous tubercles, its lateral portions nearly smooth, slightly depressed. 

 Terga of opisthosoma covered with large, low, mostly flattened tubercles, irregular 

 in shape and varying in size; the first tergum with a large polygonal central 

 tubercle encircled by smaller tubercles ; between these and the pleural sulcus there 



a 



Fig. 41. — Aphantomartus areolatus, gen. et sp. n. ; six times nat. size. — Coal Measures; South Wales. 

 Museum of Geological Survey, London, a., dorsal surface ; b., lateral view of carapace ; c, ventral 

 surface of opisthosoma. 



are several more tubercles, one of which on the postero-lateral angle of the median 

 area of the tergum is a little more conspicuous than the rest, and subcorneal ; the 

 pleural plate also tubercular, one tubercle near its middle posteriorly being a little 

 larger than the others. The succeeding terga very similarly sculptured, but with 

 the large tubercle on the pleural plate and on the admedian side of the pleural 

 sulcus still more conspicuous. These larger tubercles are not, however, present 

 apparently on the tergum of the seventh segment. 



Measurements in mm. — Total length about 9; length of carapace about 4, 

 width 5 ; length of opisthosoma 5, width a little less. 



Coal Measures of S. Wales : Mynyddislwyn vein ; Cwernan level, three- 

 quarters of a mile S.B. of Maes-y-cwmmer, and one-third of a mile E. of the Boot. 



Type, above described, Nos. 25016 and 25017 in the Museum of the Geological 

 Survey, Jermyn Street. 



There is also a specimen (No. J. P. 565a) from the same locality and formation 



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