CLBlAnxiKAlTUS. 



L87 



Figs. 120 a—c. — Climacograptus scalari 

 var. miserabilis, nov. 





Length and never exceeding 1 mm. in breadth, 

 being more commonly about "8 mm. The thecae 



are of the usual scalaris type, and number eleven to 

 ten in 10 mm. 



Affinities. — Var. miserabilis lias all the appear- 

 ance of a starved CI. scalaris, with which species 

 it agrees in the type of its thecse and the general 

 characters of the proximal end; it differs in its 

 | j smaller size and width. 



| ' ' Horizon and Localities. — Upper Hartfell Shales 



and Lower Birkhill Shales. 



IS. Scotland: Dobb's Linn, Hartfell, ete. Shrop- 

 shire : Aldress Burn. 



Associates, etc. — Var. miserabilis is most abun- 

 dant in the zone of Dicellog. complanatus, where 

 it occurs in association with the zone fossil and 

 Diplog. social is ; it is also met with in the Dicellog. 

 anceps zone associated with Dicellog. anceps, CI. 

 supemus and < 7. lotus ; while a few individuals survive into the lowest beds of the 

 Birkhill Shales, where they have been found associated with Gephalog. acuminatus, 

 Diplog. vesiculosus, and various Dimorphograpti. 

 Collections. — Lapworth and the Authors. 



Well preserved specimen, obverse 

 view. Dobb's Linn, Upper Hart- 

 fell Shales (zone of Dicellog. com- 

 planatus). Coll. Wood. 



Proximal end showing the typical 

 aspect. Ibid. Coll. Lapworth. 



Distal thecse. Ibid. 



Climacograptus rectangularis (M'Coy). Plate XXVI, figs. 5 a — e. 



1850. Diplograpsus rectangularis, M'Coy, Arm. Mag. Nat. Hist., ser. 2, vol. vi, p. 271. 



1851. Diplograpsus rectangularis, M'Coy, Brit. Pal. Foss., p. 8, pi. i, b, fig. 8. 



1876. Non Climacograptus rectangularis, Lapwortli, Cat. West Scot. Foss., pi. ii, fig. 50. 



1877. Non Climacograptus scalaris var. rectangularis, Lapworth, Crap. Co. Down, Proc. Belfast Nat. 

 Field Club, p. 138, pi. vi, fig. 32. 



1897. Non Climacograptus rectangularis, Tornquist, Diplog. and Heteroprionidae of Seaman Rastrites 

 Beds, Acta "Reg. Soc. Pliysiog. Lund, vol. viii, p. 8, pi. i, figs. 16 — 21. 



Polypary 1 — 4 cm. in length, widening steadily from 1 mm. (0*5 in relief) 



until a maximum breadth of 2'5 mm. is attained. Sicula 1*5 mm. in length 



but partially concealed; virgella conspicuous, short. Thecae of the general 



type of those of CI. scalaris, twelve to ten in 1 mm. Septum nearly complete. 



Description. — The polypary exhibits great variation in length, but the general 



characters are always maintained. The increase in breadth is gradual and almost 



imperceptible over the first 1*5 cm. of its extent; the maximum width attained 



varies between 2 mm. and 2*5 mm., but never exceeds the latter dimension. 



The sicula has a total length of 1*5 mm., but in adult specimens only 1 mm. is 



