60 



11. Onychium auratum Kaulf. 



At present named O. siliculosum C. Chr. This is a rather rare 

 kremnophytic fern, occurring throughout Java from the plains up to 

 an altitude of 2100 m. It grows almost exclusively on steep banks 

 and is reproduced only by spores. Krakatao offered it in 1886 on its 

 steep ravine-walls many fit habitats and according to Raciborski ') 

 it was in 1897 very frequent on that island. 



Of lower Cryptogams Treub found 2 mosses which he sent, for 

 determination, to Dr. Van de Sande Lacoste in Amsterdam. But 

 as this savant died shortly afterwards, these mosses have at present, 

 to my knowledge not yet been named and, most probably, are lost. 

 Besides these mosses Treub found six Scliizop/tyceae (belonging to 3 

 genera) which formed in the localities investigated almost everywhere 

 a thin greenish or glaucous gelatinous hygroscopical layer. These 

 algae were provisionnally named by Treub: Lyngbya intermedia 

 Ireub, L. minutissinia Treub, L. Verbeekiana Treub, Symp/oca spec. -), 

 Anabaena spec, and To/ypothrix spec. Of the 3 first of these species 

 Treub gave a short diagnosis. Afterwards these algae were, as 

 it seems, described by Ireub in Annals and Magazine of Natural 

 History (1898), p. 148, a work I have not been able to consult. In 

 volume V (elaborated by F o r t i, 1907) of the Sylloge Algarum of De 

 loni 2 of Treub's algae are renamed. Lyngbya minutissinia Treub 

 is reduced there (p. 335) to Hypheothrix litora/is Hansg. and Lyngbya 

 intermedia Treub (p. 275) to Lyngbya subo/ivacea Hansg. Lyngbya 

 Verbeekiana Treub I did not find mentioned in De Toni. Especially 

 Lyngbya Verbeekiana Treub and Hypheothrix litoralis Hansg, were 

 in 1886 very common in the investigated part of Krakatao. 



Treub expressly states that in the entire island he did not 

 find a single lichen. But as he examined only a small part of the 

 island we may by no means conclude from his statement that in 1886 

 lichens did not yet occur on Krakatao. 



It seems that Treub did not make researches after the micro- 

 flora of the soil and after the fauna, at least he is silent about these. 



Beneath I give a synopsis of the 34 plants found by Treub. 

 Only the 11 Polypodiaceae (No. 919) are present in the Buitenzorg 

 Herbarium. Whether of the other 23 plants materials are still extant 

 is unknown to me. 



') Die Pteridophyten der Fiord von Buitenzorg MN'.W), p. 1(14 under the name of 

 O. auriilnni A/As. 



2 ) Hy a typographical error tlie name is in Treub's pnper misspelled Symplon}, 



