107 



Penzig states that in the investigated higher parts of the 

 mountain Imperala was one of the commonest grasses, but he does 

 not say in which kind of locality it occurred, neither whether it was 

 already growing gregariously. Those parts of the ash- and pumice- 

 fields which did not bear the much more robust and more moisture- 

 needing Seccharum spontaneum may have been covered with a dense 

 vegetation of alang-alang. On the rocks this grass can have grown 

 only in deep crevices or must have been entirely absent. 



In a locality of the somewhat higher parts of the mountain 

 Penzig found many specimens of Spat/iog/ottis p/icata Bl. This is 

 a violet- or white-flowered terrestrial kremnophytic orchid of sunny 

 or slightly shadowed localities, by preference of such ones as 

 are deficient in humus; it is spread throughout West- and Central- 

 Java between 125 and 1600 m. altitude, especially above 600 m., 

 except in regions where the east-monsoon is strong. It occurs princi- 

 pally on steep banks of ravines, terraces and hollow roads, moreover 

 on rocks, in alang-fields, thickets and young secondary forests, 

 locally often in rather great numbers. In 1908 this plant was 

 frequent on vertical ravine-sides in the south-eastern part of Kra- 

 katao. 



Together with Spathoglottis, but less frequently than this species, 

 occurred in 1897 Arundina speciosa B/., likewise a terrestrial orchid, 

 which is spread throughout Java from the plains up to 1600 m. except 

 in regions where the east-monsoon is strong. It grows in the same 

 kind of habitat as Spat/iog/ottis and often intermixed with it. This 

 species also may be locally rather frequent, especially in stony 

 localities ') and in hard soils, provided the somewhat deeper layers 

 of these, in which the plant roots, do not dry out too much in the 

 east-monsoon. 



Penzig says that these two orchids were accompanied by a 

 third species, a Phajus of which he does not give the specific name 

 and of which, to my knowledge, no specimens collected in 1897 on 

 Krakatao are present in the Buitenzorg herbarium. The only species 

 of this genus found until now on Krakatao is Pha/us tankervilliae 



: ) In September 1897 it was found by Mr. A. E. Kerkhoven [See Teysmannia VII! 

 (1898) p. 506] on the very stony lower slopes of Mount Guntur (2040 rain-days in 

 the 4 driest east-monsoon months) It was found back there i.a. by Dr. A. Ernst 

 in Nov. 1905 who in his description of the vegetation (Vegetationsbilder herausgegeben 

 von Dr. G. Karsten und Dr. S c h e n c k, 7e Reihe, Heft 1 and 2, IV) wrongly calls it 

 a xerophyte. It roots in the deeper, moister layers of the soil which should not be con- 

 founded with the dry surface. See also the statement ofFransen Herderschee 

 cited on p. 102 herebefore 



