Mr. (J. Lapworth on new British Graptolites. 151 



somewhat patulous. From a point which, in the profile 

 view, appears to be a little above the central point of its 

 lateral aspect the apertural edge is prolonged into a stout 

 and stiff horizontal spine, about one twelfth of an inch in 

 length. 



Horizon and Locality. Lower Ludlow rocks of Stanner 

 Hall, near Ludlow {collected by John Hopkinson. Esq.. 

 F.G.S.). 



3. Monoqraptus Iioeineri, Barrande. 

 (PI. IV. figs. 5 a-5 e.) 



Monograptus Roemeri, Hopkinson, he. rib. supra. 



Polypary short, stout, straight, and rigid, from half an 

 inch to an inch in length, rapidly expanding from a blunted 

 proximal extremity to a maximum diameter of one eighth of 

 an inch. Virgula invisible. Hydro thecje thirty to the inch, 

 inclined at an angle of from 30° to 45°, long narrow tubes, 

 overlapping each other for about four fifths of their length, 

 and having a very oblique, slightly contracted and everted 

 aperture, destitute of visible ornamentation. 



Few examples of this species collected by myself or others 

 exceed one inch in length ; and the vast majority are under 

 half an inch. The larger examples have their margins parallel 

 in the distal moiety of their length. In the smaller examples 

 the polypary is widest near its distal extremity. The proxi- 

 mal end is bluntly rounded, rarely pointed, and the first formed 

 theca? are spinose. The normal hydrothecas are rounded tubes, 

 about one eighth of an inch in length, overlapping each other 

 throughout, except in the neighbourhood of the aperture. In 

 well-preserved examples, and in the true profile view, the 

 apertural margin is at right angles with the axis of the theca. 

 It varies much, however, in its degree of obliquity, according 

 to the slight variations in the direction of compression. There 

 is a distinct appearance of contraction below the aperture in 

 specimens in relief. The orifice itself is a little patulous, so 

 that the lower margin appears denticulate in certain views 



This is certainly the British representative of Barrande's 

 Monograptus Roemeri of the Bohemian rocks ; but whether it 

 can properly be referred to that species is open to question. 

 It has not hitherto been described from British strata. 



Horizon and Locality. Lower Ludlow rocks of Adferton 

 (Herefoi-d) (Mr. LLopkinson), Lower Ludlow of Builth (Prof. 

 Nicholson), Lower Ludlow of New Radnor and Presteign. - 



11* 



