MONOGRAPTUS. 427 



Horizon and Locality's. — Wenlock Shales (zones of Gyrtog. symmetncus and 



0. rigidus). 



Welsh Borders : Dulas Brook, near Pencerrig, Builth ; Nant Prophwyd, near 

 Builth ; Llwynrhedith Quarry, Long Mountain. Lalce District : Middle and Near 

 Gills, Cautley ; Bluecaster Gill ; River Rawthey ; Wandale Hill, etc. 



Collections. — Misses Watney and Welch, the Authors. 



Var. compactus nom. nov. Plate XLII, figs. 7 a — d. 



1900. Monograptus Flemingii, var. y, Elles, Quart. Joum. G-eol. Soc, vol. lvi, p. 403, fig. 13. 



In addition to the forms described above, there also occurs in the Upper 



Wenlock Shales a very small and compact variety. 

 Fra - 289 --^^^ ewiw ^ var - This rarely exceeds 1*5 cm. in length but has an 



average breadth of 3 mm. ; the thee® also are very 

 closely set, numbering sixteen to eighteen in 10 

 mm. 



Horizon and Localities. — Wenlock Shales (zone 

 of Gyrtog. Lundgreni, especially the lower part). 



Welsh Border : River Irfon, near Builth ; Ackley 

 Lane, Long Mountain ; Llwynrhedith Quarry, Long- 

 Mountain. Lake District: Near Gill, Cautley; 

 Middle Gill, Cautley; West Wandale, Cautley, etc. 

 °°5fi£jKSf&. ?L°it n |g. S ula ' CollecUons.-W*tney and Welch, the Authors. 



Monograptus uncinatus var. orbatus, Wood. Plate XLIII, figs. 1 a — d. 



1900. Monograptus uncinatus var. orbatus, "Wood, Quart. Joum. G-eol. Soc, vol. lvi, p. 476, pi. xxv, 

 figs. 23 A and B and text-figs. 20 a and b. 



Polypary relatively robust and somewhat flexed ; from 2 to 5 cm. in length, 



increasing gradually in breadth from '7 mm. to a maximum of about 



2 mm. Sicula conspicuous. Theca3 twelve to nine in 10 mm. ; of the 



general M. Flemingii sub-type but with rather less of the theca involved 



in a more claw-like hook. Overlap about one-half the total length. 



Description. — The polypary has a rather limp or broken-backed appearance 



after the manner of M. r ice ar to nens is, though otherwise the shape more resembles 



that of M. colonus. 



The sicula has a length of 1*0 mm. and reaches to the level of the top of th. 2 ; 

 its outer wall continues the line of the polypary much as is the case in M. 



