184 



BRITISH GRAPTOLITES. 



III. — Climacograpti in which the free 

 edge is practically straight and vertical, 

 and the apertnral margin is slightly in- 

 troverted and introtorted. 



IV. — Climacograpti in which the 



straight and vertical free edge is pro- 

 vided with a mesial spine, and the aper- 

 tnral margin tends to be slightly everted. 

 V. — Climacngrapti in which the free 

 edge is slightly inclined, and the apertnral 

 margin is thickened and spined. 



Type Glimacog. Scharenbergi. 



CI. Scharenbergi. 

 CI. Hughesi. 

 CI. minutus. 

 CI. extremus. 

 Type Climacog. innotatus. 

 CI. inn of at its. 



Type CI 'una cog. tuberculatus. 

 CI. tuberculatus. 



Group I. 

 Climacograpti in which the free edge of the ventral wall of the theca is 

 approximately straight and vertical, and the apertnral margin horizontal. 



Climacograptus scalaris (Hisinger) (Linne ?). 



Plate XXVI, figs. 1 a—c. 



Suec, Nova Acta Reg. Soc. Scient. 



pl. 



1821. Orthoceratites tenuis, Wahlenberg, Petrifacta Tell. 



Upsala, vol. viii, p. 93. 

 1837. Prionotus scalaris, Hisinger, Lethea Suecica, Suppl. p. 113, pl. xxxv, fig. 4. 

 1867. Non Climacograptus scalaris, Carruthers, Intell. Obs., p. 370, pl. ii, fig. 6. 

 1881. Climacograptus scalaris, Tullberg, Biliang. till k. Vet.-Akad. Haiidl., vol. vi, 



figs. 12—14. 

 1890. Climacograptus scalaris, Tornquist, Siljansorar. G-rap., I. Acta Univ. Lund, vol. xxvi, p. 23, 



pl. 11, figs. 12—15. 

 1893. Climacograptus scalaris, Tornquist, Struct. Diprionidse, Acta Univ. Lund, vol. xxix, p. 2, 



figs. 1—22. 

 1897. Climacograptus scalaris, Tornquist, Diplog. and Heteropr. of Scanian Eastrites Beds, Acta 



Reg. Soc. Physiog. Lund, vol. viii, p. 6, pl. i, figs. 1 — 8. 



Polypary not exceeding 2 cm. in length; having an average breadth of l - 5mm., 

 sicula 0"(> mm. in length. 1 Virgella conspicuous 

 but short. Thecae eleven to nine in 10 mm., 

 having a length of 1'5 mm., overlapping one- 

 third of their length, free outer edges straight 

 and vertical; apertural margin horizontal, lying 

 within approximately semicircular or sub-elliptical 

 excavations which occupy one-quarter of the Avidth 

 of I he polypary and one-fourth to one-third of 

 its ventral margin. Septum complete. 

 Description. — The polypary is characteristically 

 small and the breadth is attained by somewhat rapid 

 1 The visible length is given in each case. 



Figs. L18 a and b. — ClimacograpH 

 scalaris (His.). 



; ! 



Complete specimen, nat. size, fi 



Bisinger's type locality .4' MBsse- 

 berg, Vestrogotbia. Coll. Dr. J. E. 

 Mail-. 



Enlargemenl ( x 5) of the proximal 



