MONOGBAPTUS. 



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Monograptus distans (Portlock). Plate XLIII, figs. 6 a — d. 



1843. Graptolithus (Prionotiis) Sedywickii var. distans, Portlock, Gool. Report of Londonderry, p. 

 319, pi. xix. tigs. 4 a and b. 



Fig. 29(5. — Monograptus distans 

 (Portlock). 





Polypary long, slender, and irregularly but conspicuously flexed, several cm. in 

 length, and with an approximately uniform breadth of about 1 mm. only. 

 Thecae similar throughout, twelve to eight in 10 mm., of the type charac- 

 teristic of those of the more proximal part of M. Sedgwickii, though with 

 rather less overlap, and with less conspicuous spines. 

 Description. — The polypary is always conspicuously flexed and as a rule the 

 curvature is ventral, though this is not invariably the case. As with M. Sedgwickii 



the Irish specimens of M. distans are generally more 

 flexed than those from other areas in the British 

 Isles. The uniform breadth is attained fairly 

 quickly. 



The thecae throughout are of the same general 

 type; the apertural margin is mucronaie rather than 

 definitely spinose. 



Affinities. — Monog. distans has a certain resem- 

 blance to proximal fragments of M. Sedgwickii, but 

 the uniformly slender width of the polypary and 

 the characters of the thecae afford an easy means of 

 separation. 



Horizon and Localities. — Upper Llandovery (zone 

 of M. Sedgwickii). 



S. Scotland : The Corrie, Dobb's Linn, etc. 

 Wales: River Twymyn, Llanbrynmair. Ireland: Desertcreight, Co. Tyrone; 

 Limehill, Co. Tyrone; Little River, Pomeroy, Co. Tyrone. 



Associates, etc. — Mono//, distans is not uncommon in the M. Sedgwickii zone at 

 Dobb's Linn, where it occurs in association with the zone fossil, Monog. tennis, 

 Glimacog. scalaris, etc. It is met with a similar assemblage in Ireland and Wales. 

 Collections. — Geological Survey of England and Wales, Sedgwick Museum, Lap- 

 worth, and the Authors. 





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Distal thecae in low relief. Enlarge 

 ment of part of PL XLIII, fig. 6 c. 



Monograptus scanicus, Tullberg. Plate XLIY, figs. 2 a — d. 



1883 Monograptus scanicus, Tullberg, Skanes Gtrapt., ii, p. 26, pi. ii, fig. 38. 



1900. Monograptus scanicus, Wood, Quart. Journ. Geol Soc, vol. lvi, p. 479, pi. xxv, fig. 25 A and 

 B, text-figs. 22 a and b. 



