CAULOPTERIS. 151 



The British Museum specimens were brought to this country by 

 Claussen from Brazil, probably in 1841. The original stem in the 

 Museum at Rio de Janeiro, from which they were derived, has been 

 briefly described and figured by Solms-Laubach. 1 



Distribution. — Psaronius Irasiliensis is known only from Brazil. 

 The specimen figured by TJnger was found between Oeiras and Sao 

 Gongala d'Amarante, in the province of Piauhy. The locality from 

 which the stem in the Rio Museum was obtained is unknown. 



V. 9002. Plate VII. Also figured by Bennett & Murray, 

 Handb. Cryptog. Botany, p. 123, text-fig. 98, 1889. Co-type. 



Three polished slabs of the original type-specimen are registered 

 under this number, part of one being figured on Plate VII as 

 seen in transverse section. The form of the slab is oval, measuring 

 22 - 5 cm. along the greater, and 18 - 5 cm. along the smaller axis. 

 The pseudo-cortex, composed of adventitious roots, is considerably 

 larger than the central cylinder. The central cylinder, the 

 structure of which is described above, is nearly square, the 

 diagonals measuring 11 cm. 



Brazil. Claussen Coll. 



V. 5388. A small fragment of one of the above slabs, showing 

 part of the pseudo-cortex and vascular cylinder. 



Brazil. Claussen Coll. 



Genus CAULOPTERIS, Lindley & Hutton, 1832. 



[Foss. Flora, vol. i, p. 121 (explan. to pi. xlii).] 



External impressions or casts of stems of arborescent ferns, 

 possessing the Psaronius type of internal structure, and showing 

 the bark and the scars of the petioles. Petiolar scars large, oval, 

 arranged in longitudinal series, generally fairly contiguous, bearing 

 a large, concentric, closed, elliptical or horseshoe-shaped scar or 

 band, near the apex of which a Q-shaped vascular print occurs. 

 The bark between the leaf-scars shows traces of many adventitious 

 roots, like those which occur on the stems of living tree-ferns. 



Solms-Laubach (04), text-fig. on p. 23. 



