40 ORDOVICIAN AND SILURIAN BELLEROPHONTACEA. 



Horizon. — Upper Ordovician : Redliill Beds. 



Localities. — Prendergast Place and Lane, near Haverfordwest. 



Bemarhs. — No further specimens of this Welsh species have been found since 

 the above description was given bj me in 1906. The true generic position of 

 this shell is in Kokenospira as now established, and its nearest affinities are with 

 K. lingualis var. girvanensis from the Drummuck Group, as above mentioned in the 

 description of that species, and with the type of A', Ungiinlis (Salter), with 

 which it may prove to be identical. 



10. Kokenospira subdecussata (McCoy). Plate VIII, fig. 4. 



1852. Bellerophon suhdecussafus, McCoy, Syu. Brit. Pal. Foss. Woodw. Mus., fasc. ii, p. 311, pi. Il, 



fig. 25 a {non fig. 25), 

 1873. Belleroplwn suhdecussafus, McCoy, Salter, Cat. Canib. Silnr. Foss. Woodw. Mus., p. 97 (Lower 



Weulock Group [Deubiglishire Flags], Llaurwst, Denbigh), rt/612 (no7i pp. 68, 83). 



Specific Gharacters. — " Grlobose, of one and a half or two very rapidly enlarging 

 whorls, subcompressed towards the very obtusely angular or rounded circum- 

 ference; sides gibbous, umbilicus small, deep, partially exposing the whorls; 

 surface with strong transverse ridges, circling backward from the umbilicus to 

 the undefined l)and, forming a wide V-shaped sinus (about four or five of these 

 transverse ridges in the space of one line near the mouth) ; they are crossed by 

 much finer spiral striae, about the same distance apart, from one to three of which 

 are usually stronger than the rest near the band. . . . Rare in the schists 

 of Llaurwst; and fine Bala Sandstone, Mulock [.siV] Quarry, Dalquorhan, near 

 Girvan, Ayrshire ; not very uncommon in the Upper Bala rock of Allt yr Anker, 

 Meifod, Montgomeryshire." 



Horizon. — Wenlock Series : Denbighshire Flags. 



Locality. — Llanrwst, [a/()12, Sedgw. Mus. Camb.] 



Remarks. — The above is McCoy's diagnosis of the species, but it is a composite 

 one based on specimens from the three different localities and horizons. The type 

 of the species should apparently be the specimen from Llanrwst (n'/612, pi. i l, 

 fig. 25a), of which McCoy only figures a portion of the ornament ; Llanrwst is the 

 first locality mentioned and the description of the ornament is undoubtedly derived 

 from this shell. Unfortunately the specimen only consists of the hollow impression 

 of the exterior of a portion of the outer whorl, but it shows the shape of the whorl, 

 the slit-band, and transverse and spiral striae. The Mulloch specimen (pi. i l, fig. 25) 

 is a nearly complete shell, but is much crushed and distorted ; it shows a rather 

 different ornament and a very narrow slit-band poorly preserved, and the shell 

 seems to have been more globose with a broader and less arched dorsum ; it was 

 not collected from the Mulloch Hill Group (Llandovery) judging from the character 



