. Bulletin of the British Museum (Natural History), Geology. 210 R. A. FORTEY & R. M. OWENS Lectotype (here selected). GSM 49670, cephalon. Type locality and horizon. Whitlandian Stage, Gymnostomix gibbsii Biozone; south side of St David's Head (presumably Pwlluog, vicinity of Iocs 61D and F), Dyfed. Material. Cranidia and cephala from type stratum, Pwlluog, Iocs 61C-F. Stratigraphical range. Whitlandian, G. gibbsii Biozone. Diagnosis. Approximate distribution of pits as follows: 17-19 radii per half-arc, El5 E2 com- plete; In, Ix 0-16 or 17, I2 (?)6â16; interradii in, il? ii-vi, xii-xv; i
. Bulletin of the British Museum (Natural History), Geology. 210 R. A. FORTEY & R. M. OWENS Lectotype (here selected). GSM 49670, cephalon. Type locality and horizon. Whitlandian Stage, Gymnostomix gibbsii Biozone; south side of St David's Head (presumably Pwlluog, vicinity of Iocs 61D and F), Dyfed. Material. Cranidia and cephala from type stratum, Pwlluog, Iocs 61C-F. Stratigraphical range. Whitlandian, G. gibbsii Biozone. Diagnosis. Approximate distribution of pits as follows: 17-19 radii per half-arc, El5 E2 com- plete; In, Ix 0-16 or 17, I2 (?)6â16; interradii in, il? ii-vi, xii-xv; i2 at least xii, xiii, xiv. Glabella and genal lobes apparently smooth. Description. The small amount of material available of this species is all indifferently preserved and variously distorted. The proportions of the glabellar and genal lobes are like F. radix. The fringe differs in that the individual pits are larger, there are fewer radii, a greater number of interradii, and no 13 in the I series; there are fewer irregular pits on the posterolateral corners. Remarks. Whittard (1955: 34) remarked on the difference in the I series of pits between F. sedgwicki and the type species of Bergamia, B. rhodesi, and only placed sedgwicki in Bergamia with considerable doubt. These same characters of the I series are very similar to those of F. radix, and are noted above. Whittard (1955: 31) suggested that trinucleids from the Whitlandian of Dwyrhos, Aberdaron and Nant-y-Gadwen, Llyn Peninsula, may belong to Myttonia, but noted that the external pits in the upper lamella appear to occur in sulci. We have obtained and examined further material. '%} 1 i ( - â * â > ****'> % â 'â â¢* â n - - ^ &sfi**^ .4" ^3 & -TJf^-i'jL rf^f **» â¢M r ;*i j ? *v. Jr A - i"s j " i yi§& ! .- %i -. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illu
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