Structure and Affinities o/ Matonia pectinata, # 6> - 439 



products, in the gastric gland. Whether it is utilised for the produc- 

 tion of other pigments or not is a question for future investigation. 

 That it is a chlorophyll derivative I now believe to be proved. Its 

 stability, as compared with plant chlorophyll, is due to the fact that it 

 has been altered by the action of the digestive juices. Such derivatives 

 of complex mother-substances are, as is well known, much more stable, 

 and less prone to change than the parent pigments. 



" On the Structure and Affinities of Matonia pectinata, R. Br., with 

 an Account of the Geological History of the Matoninere." 

 By A, C. SEWARD, F.E.S., University Lecturer in Botany, 

 Cambridge. Received February 28, Read March 9, 1899. 



(Abstract.) 



The genus Matonia has long been known as an isolated type among 

 existing ferns. It is represented by two species, M. pectinata R. 

 Brown and M. sarmentosa Baker, both confined to the Malayan 

 region. Matonia has not hitherto been examined anatomically, and 

 its reference by several writers to an intermediate position between 

 the Cyatheacese and Gleicheniacese, is based on the structure of the 

 sorus, which, in the small numbers of sporangia and in its circular form, 

 resembles the latter family, while the presence of an indusium and the 

 position of the annulus afford connecting links with Cyatheaceous 

 ferns. 



In Matonia pectinata the frond has a characteristic pedate habit, with 

 numerous long pinnae having slightly falcate linear segments, practi- 

 cally all of which appear to be fertile. The sori are circular in form 

 and indusiate, consisting of about eight large sporangia with an oblique 

 incomplete annulus, containing sixty-four tetrahedral spores. The 

 dichotomously branched rhizome, which grows on the surface of the 

 ground, is thickly covered with a felt of multicellular hairs, and gives 

 rise to long-stalked fronds from its upper face, and a few wiry roots, 

 which may arise from any part of the surface of the stem. 



The full paper deals more especially with the anatomical structure 

 of Matonia pectinata. The material which rendered the investigation 

 possible was generously supplied by Mr. Shelford, of the Sarawak 

 Museum, Borneo, to whom the author wishes to express his hearty 

 thanks. 



The stem is polystelic, and of the gamostelic type ; there may be 

 two annular steles, with the centre of the stem occupied by ground- 

 tissue, or in shorter branches of the rhizome a third vascular strand 

 may occupy the axial region. Each stele consists of xylem tracheids 

 and associated parenchyma, surrounded by phloem composed of large 

 sieve-tubes, with numerous sieve-plates on the lateral walls, and phloem 



