MONOGRAPTUS. 



369 



Figs. 240 a — d. — Monograptiis concinnus, 

 h-Ainv. 



(I 



a b c d 



a. Thecaj of proximal portion. Part of speci- 



men on same slab as PI. XXXVI, fig. 5!;. 



b. Ibid. 



c. Distal tbecce. Enlargement of part of 



PI. XXXVI, fig. 5e. 



d. Distal thecaj in relief, probably referable to 



tiiis species. Eheidol Gorge, 420 yds. 

 E.S.E. of Bryn-chwith Fann house, Pont 

 Erwyd, Cardiganshire. Geol. Survey of 

 England and Wales. 



strongly resemble those of M. Nilssoiil, but 

 may be distingnislied l)y the more closely set 

 thec£e and by tlie different curvature of tlie 

 proximal portion of the polypary. 



Horizon and Localities. — Llandovery (Birk- 

 liill Shales), zones of M. gregarius to M. 

 Sedgwicldi. 8. Scotland : Dol)b's Linn ; Bel- 

 craig Burn; Garple Linn, etc. Wales: Pont 

 Erwyd (various localities) ; Pary's Mountain, 

 Anglesea. Lake District : Skelgill, etc. 



Assoriafes, etc. — Monog. concinnus appears 

 first in the M. gregarius zone, but is commonest 

 in the zones of M. conrolutus and M. SedgiuicJcii, 

 where it is associated with Monog. conuolutus, 

 M. tennis, M. Sedgu-ickii, Gephalog. cometa, 

 Glyptog. serraius var. barhafus, and other forms. 



Collections. — Geological Surveys of Scot- 

 land, and of England and Wales, Jones, Greenly, 

 Lap worth, and the Authors. 



I. A. 1. (r) : Monograjiti in which the thecjfi are uniform and the polypary has 



dorsi-ventral curvature. 



Monograptus Nilssoni (Barrande). Plate XXXVII, figs. 1 a- 



1850. GraptolHhus Nihsovi, Barrande, Grapt. de Bohcme, p. 51, pi. ii, fig. 16. 



1852. Mono(jvai)ius Nilssoni, Geiuitz, Die Graptolitlieu . . . der Grauwackeuformation iu 



Sachseu, p. 35, \A. ii, fios. 17—20, 24, 25, 28—32 (?). 

 1869. Monoijra^dus Nilssoni, Heideuliaiii, Zeitschr. d. deutsch. geol. Gesellscli , vol. xxi, p. 147, pi. 



i, fig. 2. 

 1876. Monograytus Nilssoni, Lapwortli, Geol. Mag., dec. ii, vol. iii, p. 315, pi. x, figs. 7 a — c. 

 1876. 3fonograptus Nilssoni, Haupt, Die Fauna des Graptolitliengesteines, p. 21, pi. iv, fig. 3 (?). 

 1878. Monograptus Nilssoni, Kayser, Die iiltesten Devon- Ablageruu gen des Ilarzes, p. 217, pi. xxxi, 



fig. 12 (fig. 25 ?). 



1883. Monograptns Nilssoni, TuUberg, Sk8,nes Graptoliter, pi. i, figs. 31, 32. 



1884. Monograptus Nilssoni, J. D. La Touclie, Handbook to the Geology of Shropshire, p. 78, pi. 

 xviii, fig. 576. 



1885 ?. Monograytns scanicns, Eoemer, no7i TuUberg, Lethsea Erratica, pi. ix, figs. 13 a, b. 



1889. Pristiograptus Nilssoni, Jaekel, Zeitschr. d. deutsch. geol. Gesellsch., vol. xli, p. 673, pi. xxviii, 

 fig. 7. 



1890. Monograptus Nilssoni, Geinitz, Die Graptolithen d. k. Min. Mus. in Dresden, p. 13, pi. a, fig. 

 7 (in part), nou fig. 8. 



