116 OTOZAMITES. 



imperfect to form the basis of a satisfactory diagnosis. The type- 

 specimen consists of a torn and incomplete piece of a frond, with 

 a broad rachis giving ofi short and broad segments traversed by 

 parallel veins, -which occasionally fork and are connected here and 

 there by oblique branches. The veins are, on the average, rather 

 more than 1 mm. apart. 



I have no doubt as to the specific identity of the specimen 

 figured by Buckman from Sevenhampton as Ci/cadites? with the 

 type-specimen of Brongniart. 



Ctenis latifoUa differs from the Inferior Oolite species C. fahata ' 

 in its shorter and broader segments ; as regards venation-characters- 

 the two forms are identical. An imperfect leaflet, which I described 

 as Ctenis, sp., from a specimen in the Manchester Museum,^ may be 

 compared with the Stonesfield type, but we have not suflScient 

 data from which to decide as to their possible identity. A form of 

 Ctenis frond similar to C. latifolia has been described by Eaciborski 

 from the Lower Jurassic rocks of Cracow as Ctenis Zeyschneri^ 

 which is no doubt a closely allied plant ; another similar type is 

 represented by Ctenis ormallensis,^ a species figured by Lester 

 Ward from the Jurassic beds of Oroville, California. It is by no 

 means unlikely that the Stonesfield plant is specifically identical 

 with the American form, but until better specimens are obtained 

 it is impossible to make a more definite statement as to the position 

 and characters of the Stonesfield type. Phillips includes Ptero- 

 phyllum eomptum, Phill. \_ = Nilssonia eompta (PhUl.)], in his list of 

 Stonesfield species ; it is possible that he applied this name to Ctenis 

 latifolia. 



Genus OTOZAMITES, Braun. 



[Miinster, Beit. Petrefact. Heft vi. p. 36, 1843.] 



Otozamites, sp. 



[Cf. 0. ohtusus (L. & H.), var. oolitictts.'] 

 The Museum collection includes a few imperfect and obscure 

 specimens of Otozamites fronds, which are too small and indistinct 



» Seward (00), pi. viii. %. 2. 



2 Seward (00), p. 232, fig. 42 ; also (00^), pi. ii. 



' Eaciborski (94), pis. ivi.-xvii. 



* "Ward (00), p. 357, pi. Iriii. fig. 4. 



