BY THE REV. J. E. TENISON- WOODS, F.G.S., F.L.S. 79 



form shows the closest analogy to our Indian Vertebraria. About 

 the identity of the genera there is no doubt; the species are 

 perhaps different, Dana's Clasteria is nothing else but Vertebraria. 

 It represents the longitudinal section of the same plant of which 

 V. australis as figured by M'Coy, formed the transverse section, 

 an analogous case to that of India where V. inclica was the longi- 

 tudinal section and V. radiata the transverse section of the 

 same plant, In Australia it is described from the upper coal 

 measures only. Unger placed both the Indian and Australian 

 Vertebraria with Sphenophyllum. This is an error which everybody 

 will perceive from the figures. Quite lately Vertebraria (f) 

 petsehorensis was described by Schmalhausen (loc. cit. p. 53, tab. 

 vii., figs. 14 and 18) from Jurassic beds of the Petschora country 

 (Oranetz, on the right bank of the Petschora river), but so far as 

 I can judge from the drawings, his specimens do not show much 

 relation with the Indian or Australian Vertebraria." 



Dr. Feistmantel goes on to say that the one Indian species of 

 Vertebraria is known from all divisions of the Lower Gondwana 

 beds, and from almost all horizons, which would according to the 

 same author make them the equivalents of our Hawkesbury rocks 

 and shales. 



If we take it as established that Vertebraria is an Equise- 

 taceous root, I think the fossils might be expected to have as wide 

 a range as the Equisetina?. Such is the case in Australia. They 

 have been hitherto regarded as restricted to the Newcastle beds, 

 where they are generally underneath strata containing Phyllotheca. 

 These Vertebraria, I think, can be distinguished from those asso- 

 ciated with Equisetum. I have found Vertebraria in all the 

 lower shales of the Ipswich coal measure, which I shall refer to 

 presently. First, however, let me mention what is known of the 

 rhizome of a true Equisetum. 



Taking the figures as given by Schimper from Bischoff (D. 

 Krypt. Gewachse, tab. III.), we find that in the living Equisetum 

 arvense Linn, there is a long creeping root with distant 

 parallel grooves, diaphragmata, and sheaths, all on a larger and 

 coarser scale than on the living stem. At intervals there are 



