108 



Bl. (Ph. blumei Lindl., Ph. incarvillei O.K.) which in May 1908 was 

 found here and there on the south-eastern side of Krakatao in 

 humid and not very dark ravines between 200 and 400 m. above 

 sea-level. If and such is highly probable - it was this same species 

 which was collected by Penzig in 1897, it did certainly not grow 

 in the company of Spathoglottis and Arundina, i.e. in oecologically 

 equivalent localities. For Phajus tankervilliae BL, a terrestrial orchid 

 rather common in West-Java between 500 and 1200 m. above sea- 

 level, is no kremnophyte but a mesophyte, it occurs on water-sides, 

 in humid localities either stony or not and covered with grass or 

 shrubs, less often in dense forests but never on the sterile walls, 

 steep banks or sunny alang-fields preferred by the two other species 

 mentioned by Penzig. The possibility remains that Phajus was 

 growing on the bottom of a ravine, Spathoglottis and Arundina in 

 its vicinity on ravine-sides or on fields of ashes and pumice. The 

 oecological difference between the bottom and the sides of a ravine 

 was already discussed herebefore (p. 105). 



It is worthy of note that from investigations made by Forbes 1 ) 

 appears that often autogamy takes place with the 3 species of 

 orchids collected by Penzig-). There might be some connection be- 

 tween this fact and the abundance of Spathoglottis in 1897. Penzig 

 gives no information about any insects having been found that might 

 effect pollination. 



Finally several specimens, often of more than one meter high, 

 were found of Blumea balsamifera D. C. ,,und mehrere dieser 

 verwandten Formen". For Blumea balsamifera see p. 51. One of the 

 ,,allied forms" was probably Erigeron /inifo/ius, as appears from a 

 specimen preserved in the Buitenzorg Herbarium, wrongly recorded 

 in P e n z i g s list under the name of Blumea hieracifolia. For this 

 plant see p. 51. Neither Blumea balsamifera nor Erigeron linifolius 

 lays high claims to the fertility of the soil, both may have been col- 

 lected on arid ridges though they also occur in more fertile localities. 

 Penzig says nothing definite about the habitat. Another ,,form" 

 allied to Blumea ba/samifera is Pluchea indica Less, (see p. 50), a species 



') Forbes, A Naturalist's Wanderings in the Eastern Archipelago (1885), p- 85 

 seq. and K n u t h, Handhuch Bliiten biologic III 2 pp. 316, 318. 319. 



2 ) With Phajus tankervilliae the same experience was made by |. |. Smith [see Die 

 Orchideen von lava (1905), p. 196): ,,Bei alien von mir gesehenen Exemplaren fand 

 ,,Selbstbefruchtung statt." - From an observation made by j. Krajenbrink [see De 

 Tropische Natuur XVII (1928), p. 132 seq,] appears that, though autogamy takes place 

 as a rule, there are some specimens that are non-autogamous. Smith has observed 

 the latter particularity with specimens from Sumatra. 



