CLIMACOGRAPTUS. 



201 



Var. bursifer, var. nov. Plate XXVII, figs. 6 



d. 



a. Proximal end showing- disc. Enlarge- 



ment of part of PI. XXVII, fig. 6 c. 



b. Distal thecse. Enlargement of part of 



specimen on same slab as fig. 134 a. 



A variety of CI. antiquus which is occasionally 

 met with in the Glenkiln Shales differs from the 

 typical form in possessing more closely-set thecse, 

 and in having the membrane connected with the 

 proximal tube swollen out into a sac at some distance 

 from the polypary. 



The thecas number fourteen to twelve in 10 mm. 

 and have their ventral walls distinctly inclined ; the 

 sac is fully 6 mm. below the sicula. 



Affinities. — Var. bursifer presents obvious resem- 

 blances to CI. Wilsoni, but differs (1) in having the 

 sac at a greater distance from the polypary and 

 (2) in the characters of the thecas, whose ventral 

 walls are more inclined and the apertures more 

 introverted. 



Horizon and Localities. — Glenkiln Shales and 

 their equivalents. 



8. Scotland : Kirkmichael Burn. Wales : Tid- 

 dyndiewm. 



Associates, etc. — Those of the typical form. 



Collections. — Lapworth and Fearnsides. 



Var. lineatus, var. nov. Plate XXVII, figs. 5 a—f. 



Figs. 132 a, b, and c. — Climacograptus 

 antiquus, var. lineatus, nov. 







ate 



Proximal end showing basal spines. 

 Enlargement of part of PI. XXVII, 

 fig. 5 a. 



Distal theca;, showing profile of exca- 

 vations. Enlargement of part of PI. 

 XXVII, fig. 5 b. 



Distal thecne. Enlargement of part 

 of specimen on same slab as PI. 

 XXVII, fig. 5e. 



Another variety of CI. antiquus, which occurs 

 at a slightly higher horizon than the typical form 

 and is characterised by its extreme length, may be 

 appropriately distinguished as var. lineatus. In 

 this variety the polypary may have a length of 

 8 cm. but never exceeds 2 mm. in breadth ; 

 the thecae are rather more distant than in the 

 typical form, numbering only eight to nine in 10 

 mm. ; in other particulars they agree with those 

 of CI. antiquus itself. 



Horizon and Localities. — Upper Glenkiln 

 Shales and Lower Hartfell Shales. 



8. Scotland : Craigmichan Scaurs. Wales : 

 Llanystwmdwy ; Conway ; Spittal Road Cutting. 



Collections. — Fearnsides; Sedgwick Museum. 



