Manchester Mevioirs, Vol. xiviii. (1903), No. ^. 11 



the preservation is not sufficiently good to warrant more 

 than a somewhat doubtful reference to this type of pith 

 cast. Calaviites decoratiis is identical with C. Suckotvi. 

 Salter and Binney have recorded C. cminceformis Schl., 

 but this species is a most unsatisfactory one with no 

 clearly defined scientific characters\ These determinations 

 are therefore of little value. 



Note on Poacites sp. 



Both Binney and Salter have recorded from Ardwick 



certain specimens under the name Poacites, probably on 



account of a certain similarity between their fossils and a 



figure of an imperfect plant, also from the Lancashire 



Coalfield, described by Lindley and Hutton in their. 



Fossil Flora as Poacites cocoina." The genus Poacites v^diS 



originally founded by Brongniart for the reception of 



certain Tertiary grass-like remains, to which Lindley and 



Hutton's specimens presumably bore some resemblance. 



Their type specimen is now in the British Museum^ ; and 



I agree with Mr. Seward* who has suggested that it is 



simply a badly preserved portion of a Calamite with very 



long internodes. Some of Binney's specimens (Nos. 596 



and 1 1 24) bear a very striking resemblance to Lindley and 



Hutton's plant, and are certainly only badly preserved 



Calamitean pith casts. One of these consists of stems 



with long internodes, the ridges and grooves of which are 



very much worn, and the structural characters of the nodes 



almost entirely obliterated. This deformation seems to 



have arisen as the result of rock movements which have 



given rise to slickensides. Evidence of such thrust-planes 



^Kidston ('91), p. 364. 

 ^Vol. II., pi. CXLlib. 



''British Museum (Nat. Hist.), Geological Department, Registered 

 Number, V. 4304. 



^Seward ('98), p. 366. 



