8y8 C. SKOTTSBERG 



north of Inocentes (Pis. 105, 108:2; comp. p. 18). More robust than the former, 

 with the rather clumsy trunk as a rule 2 — 3 m long and often with one or a few- 

 branches. The specimen figured by Johow (pi. XVIII), measured 4.5 m (p. 287), 

 but much taller ones are occasionally seen; thus the largest measured by us, illus- 

 trated on PI. 2 (this vol. no. 7), was 6.5 m tall and undoubtedly very old, as the trunk 

 measured about 1.5 m across the enlarged base and 6"] cm below the first living 

 limb; there were 6 branches, 2 of them dead. An average-sized frond has a pet- 

 iole about 50 cm long and 4.5 cm broad at base and a blade of about 1,3X1 m. 



BlecJumm cycadifoUiim (Colla) Sturm. Endemic and common on both islands, 

 particularly abundant on the windswept ridges, where it is one of the leading 

 plants in the scrub; extends from near sea-level to the most elevated crests in 

 Masatierra, ranging west to Bahia Chupones. Less frequent on ]\Iasafuera but 

 ascending above the timber-line to near the summit; see also p. 28. Johow 2 p. 

 244 says "apenas arborescente", but in my opinion it grows to become a true 

 tree-fern; the trunk, often low and curved, will be well over i m tall in the forest 

 and 15 — 20 cm thick. The rigid, dark green and lustrous fronds give to this 

 plant a striking Cycas-XxV^ appearance (PI. 4, this vol. no. 7; pis. 58:2, 84). 



Thyrsopteris elegants Kze. Endemic. Masatierra, not uncommon in the mont- 

 ane woods from Rabanal to Valle Ingles; descends on the Villagra side to about 

 175 — 250 m above sea-level. Masafuera, apparently confined to the highland, 

 where it reaches iioo m; see also p. 16. Ascends from a clumsy, prostrate rhi- 

 zome, passing into an erect trunk raising the canopy of magnificent fronds well 

 over man's height (PI. 81). A frond lasts 2 years. The trunk may reach i m, 

 but is as a rule shorter; thickness about 20 cm. Very large fronds (Masatierra) 

 with stipe 1.7 — 2.5 m and, blade 1.3 — 1.75 m, as wide or a little narrower. A 

 small fertile frond is figured in Skottsb. j, pi. 7:4. The sporangia-bearing seg- 

 ment developes during the summer and reaches maturity in March. 



LopJiosoria quadripvinita (J. F. Gmel.) C. Chr. Cyatheaceae. A form of this 

 widespread species is one of the commonest ferns in the islands, ranging from 

 the ravines in the deforested valleys to the highest wooded ridges in Masatierra 

 and a dominant on the highland of Masafuera. Johow states p. 154 (Alsophila 

 pruinata Kze) that the trunk attains a length of 2 m and a thickness of 15-20 

 cm. We have never seen specimens of this size, and I am convinced that they 

 must have been exceptional. Even if a trunk is developed, it is as a rule much 

 shorter, considerably less than i m. The fronds are very large, to 3 or sometimes 

 4 m long. The stunted form growing in the Subalpine-Alpine region on Masa- 

 fuera is seen on PI. 115:1. 



Dryopieris inaequalifolia (Colla) C. Chr. Endemic and common in the forests of 

 both islands, and not rare in many places on the deforested slopes. The erect 

 trunk generally remains quite short but will reach a height of ^/o or perhaps i 

 m under favourable conditions. The fronds attain a length of 2 m (PI. 3, this 

 vol. no. 7). 



