486 DR F. A. BATHER. 



§ 526. The rectal lobe descends in the holotype to below the third flange ; the lobe 

 on the other side to the top of the second flange. The rectal lobe is broadly rounded 

 and its whole outline is not very clearly seen, but its width at the level of the stem- 

 facet is fully 9 "5 mm., its length below the stem-facet is 4*4 mm. as measured on the 

 outer surface, and 6*8 mm. as measured on an imprint showing the inner surface of 

 the theca and of the stem-lumen. The former measurement is the one that serves for 

 comparison with other species, and the length may therefore be taken as not more 

 than half the width. 



§ 527. The Pectinirhombs are all well developed, and all provided on their adcentral 

 sides with sharp borders, which rise in a steep concave curve from the relatively 

 smooth surface of the plates ; the outer borders are more gently rounded. 



Pectinirliomb 1-5 in Gl72 is almost lozenge-shaped, with sutural axis, 3'8 mm., 

 transverse axis, 5 "8 mm.; it has about 16 folds, which appear to be slightly closed by 

 stereom on plate 1. In Gl77, plate 1 is slightly shifted over plate 5, so that the 

 rhomb has acquired a trapezoidal outline approaching a square; it has 19 folds, more 

 clearly seen in plate 5. 



§ 528. Pectinirliomb 10-14 (text-fig. 71) is approximately kite-shaped, having the 

 obtuse angle at its adoral end, and the larger half of the rhomb on plate 14. In 

 Gl72, sutural axis, 9*9 mm. ; transverse, 77 mm. ; in Gl77 the plates are shifted, but 

 the measurements seem to have been almost the same. There are about 50 folds, almost 

 entirely closed by stereom on plate 1 4. In both specimens this rhomb is nearer the 

 lower end of the suture. 



§ 529. Pectinirhomb 11-12 is not preserved in the holotype, and is not clearly seen 

 in (t177 ; its long axis occupied more than half the suture in approximately its middle 

 tract, and about 25 folds can be counted. 



The folds in all the rhombs appear regular, and do not exhibit intercalation or 

 fanning out (cf. §§ 455, 510). 



§ 530. The Periproct is wide. In the holotype, plates 12 and 14 may perhaps 

 just have met by their extreme tips (PI. VI. fig. 68) ; in G177 they do not appear to 

 have met (PI. VI. fig. 64). 



§ 531. The Periproctals are exceedingly obscure in Gl72, but it appears certain 

 that none exceeded '9 mm. in diameter. In Gl 77 their diameter is ca. '5 mm.; a 

 few may possibly have been a trifle larger, but others are smaller. 



The Vent is not distinguishable. 



§ 532. The Ornament of the antanal face consists of small granules with a 

 concentric arrangement, but also forming fine, faint, granular rhomb-ridges of which no 

 one is specially prominent. There are also broader, obscurer radiating ridges. The 

 whole ornament is very fine and equable, so that the surface appears almost smooth 

 to the naked eye. 



§ 533. Of the Stem, three stout flanges are seen in the antanal face of the holotype, 

 occupying a length of 4*7 mm. ; with a diameter of 5 '7 mm. The proximal flange is 



