as well as on the Island of Lanai on the main ridge of Haalelepakai, from which 
place it had not been reported previously. Hillebrand in his Flora reports 
Pterotropia dipyrena from Lanai, especially from the main ridge; the writer, 
however, failed to find a single tree of this species, but Tetraplasandra hawaii- 
ensis being very common he comes to the conclusion that there is a possibility of 
Hillebrand having mistaken the identity of the trees in question, which resemble 
each other very much and perhaps could be mistaken one for the other when 
not in flower. 
The middle forest zone is also the home of the loganiaceous genus Labordea, 
of which many species exist, as new ones have come to light since the explora- 
tion of this group has been commenced systematically. Mention must also 
be made of the extraordinary species of Compositae belonging to the genus 
Hesperomannia. Mr. Forbes has described an interesting species which he 
found on the Island of Kauai, and the writer has found trees 30 feet in height 
of H. arborescens on Mt. Konahuanui, Oahu. The trees were originally 
found on the Island of Lanai on the highest ridge, where Hillebrand says he 
found about eight specimens of this tree. Dr. R. C. L. Perkins told the writer 
that he found two trees about ten years ago. A careful search during a six- 
weeks’ stay on that island did not reveal even a sign of such a tree once having 
existed. Our three species of Hesperomannia are very closely related to the 
Tahitian Fitchia, a genus of two arborescent mountain species. 
Of Goodeniaceae, several species belong to this region, Scaevola mollis being 
peculiar to Oahu, as well as S. chamissoniana, the latter, however, descending 
into the lower forest zone, while S. procera inhabits the mountains of Molokai, 
Maui, and Kauai; 8. cylindrocarpa being only found on Lanai on the highest 
ridge. The epacridaceous shrub, Styphelia tameiameia, is also an inhabitant 
of this zone, together with Vaccinium penduliflorum. 
Of herbaceous plants, several species of Campylotheca belong here, as well 
as several vines, as Gynopogon oliviformis (Maile), the liliaceous Smilax sand- 
wicensis (Pioi), and the myrsinaceous Embelia pacifica. Besides Euphorbia 
Rockii, a number of other species belong to this zone, such as E. clusiaefolia and 
E. multiformis, the former on more exposed ridges, especially back of Honolulu 
on one of the ridges leading to Konahuanui, where it is associated with a stunted 
form of Syzygium sandwicense (Ohia ha). 
Of Violaceae, Viola robusta, a very stout species 3 to 5 feet tall, is very com- 
mon in the dense, mossy forest, while V. Chamissoniana, a shrubby species with 
pink flowers, is found mainly along stream beds (see Plate XXI) in company 
with shrubby species of Plantago, such as Plantago princeps, not uncommon 
back of Kamoku camp, Molokai, where it grows over 6 feet tall. The Labiatae 
take here also an important place, Phyllostegia being represented by numerous 
species. Especial mention must be made of the truly superb specimens of Ste- 
nogyne Kamehamehae, which trail over the swampy ground with large clusters of 
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