BRITISH GRAPTOLITES. 



Bryograptus Kjerulfi, Lapworth. Plate XII, figs. 3 (/, h. 



1880. BryoijrajitHs Kjerulfi, Lapworth, Ann. Mag. Nat. Hist. [5], vol. v, p. 1(34, pi. v, fig. 22. 

 1882. Bnjograjjtus Kjerulfi, Brogger, Die Silur.-Etagen, 2 u. 3, p. 37, pi. xii, fig. 20 a. 

 1898. Bryographis Kjerulfi, EUes, Quart. Journ. Geol. Soc, vol. liv, p. 4()9, fig. 1. 



Main stipes short, r2 to 2 cm. in length, and not exceeding 1 mm. in width; 

 diverging from a conspicnons sicula at a small angle, and growing sub verti- 

 cally downward ; from their inner or thecal margins originate two or more 

 symmetrically disposed compound lateral branches. Thecee eight to nine 

 in 10 mm., inclined 20°, having an average length of 1"5 mm., four times as 

 long as wide, inclining slightly in the direction of their apertures, over- 

 lapping one third their length, and having their outer walls slightly curved. 

 Apertural margins concave. 

 DescrijMoji. — The polypary is always short ; Lapworth gives the angle of 

 divergence of the main stipes as 40°, but it often appears larger owing to the mode 

 of preservation. The lateral branches are symmetrically disposed, — that is to say, 

 they are given off at similar distances on either side of the main stipes. 



The sicula has a length of I "6 mm., and from its 



Fio. 50.— Bryograptus Kjerulfi, 



Lapworth. apcx a line thread-like prolongation (the nema or 



virgula) is often seen to extend. 



Affinities. — Br. Kjerulfi. is characterised by its 

 shrub-like form, and by the fact that the main stipes 

 have a tendency to run parallel to each other in a 

 manner which forcibly suggests the lial^it of the later 

 " tuning-fork " Graptolites. 



It resembles its variety oimhrensis in the general 



Proximal end, showin-frcHiuent branch- shape and characters of the thecce, but differs in the 



^^^:'^'^.Jt7iS^ symmetrical disposition of its lateral branches. From 



Snlad^siab i^'AT^alnlT ^r. dhcTgcns it differs in the direction of growth of 



the main stipes, and from Br. ramosus, Brogger, in 



the number of thecal in a given unit of length. 



Horizon and LocalltleH. — Tremadoc ? Lower Skiddaw Slates (Br yog raj) tits beds). 

 Lake District : Barf. 



Associates, etc. — Br. Kjerulfi', occurs in the Lower Skiddaw Slates of the Lake 

 District associated Avith var. cumhrensis. The species has a gregarious habit, as 

 may be seen from the slab figured on IM. XII, fig. 3 h. 



The best specimens known to us are iu the collections of the Jermyn Street 

 Museum, Po.stlethwaite, and Mr. W. A. lireud. 



