185 



237 



rachis. Pinnæ opposite or nearly so, sessile 8 — 9 cm long, l'/2 — 2 cm broad acu- 

 minate, the basal pair deflexed and narrowed towards their base, the upper ones 

 divaricating and broadest at the base, ciliate, the costæ above strigose, the upper- 

 side glabrous or very slightly and shortly hairy, costæ and costulæ beneath with 

 patent, simple hairs, the underside otherwise nearly glabrous. Segments oblique or 

 subfalcate, obtuse or subacute, the lower ones of the basal pinnæ short. Veins 

 simple, 10 — 11-jugate, the lo- 

 wer 2 running to the sinus, 

 where their apices are se- 

 parated by a pale mem- 

 brane. Sori medial, with a 

 pilose, persistent indusium. 

 Sporangia glabrous. 



The diagnosis above is 

 of the original specimen. 

 With this agree a large lîum- 

 ber of specimens from South- 

 ern Brazil in almost all cha- 

 racters, although I have not 

 seen another specimen, which 

 exactly matches the original 

 one, but it is sure that all 

 these specimens belong to 

 the same species, which is 

 evidently very common from 

 Rio to Rio Grande. Several of 

 the specimens were labelled 

 Nephrodium tetragonum Hk. 

 resp. Dryopteris pseudotelra- 

 gona Urb., others Polypodiiim 

 tetragonum. From the an- 

 dine form of the former as 

 previously understood, now 

 I), gemmulifera Hieron., D. 

 scabra differs by the short pinnatifid apex of the lamina, from the latter, which it 

 resembles in habit and colour, by its free veins, sessile pinnæ and its pinnatifid 

 apex without a distinct terminal pinna. 



I), scabra is a very variable species; the specimens seen can be grouped as follows: 



var. incompleta (Lindm.) 



Syn. Polijpodium tetragonum var. incompletum Lindm. Ark. for Bot. 1: 229 

 tab. 9 fig. 7. 1903. 

 Dryopteris pseudotetragona \ar. foecunda Rosenst. Hedwigia 46: 119. 1906. 



Fig '.i'i. D. scabra (I'r.) C. Chr. leg. Pohl. Basal pinnæ, middle pinna 

 and apex of leaf X ^(s; segments seen from both surfaces X !'/'-• 



I). K. U. Vidensk. Selsk. Skr., 7. Række, naturvidensk. og niiithem. .\fd. X. 2. 



31 



