68 



species of the section jxihiiacfonius. as Vyanea hptosfcuia, C. sxpcrba, C. ar- 

 hurai. and V. (jiffanJii are the oldest denizens and that 1hey are on the verge 

 of extinction, while others are to he considered in their prime and still in the 

 process of evolntion. 



THE GENUS DELISSEA. 



I'nfortunately the s;)ecies of Dclissea are not so well known as the species of 

 Cyanea and Clcnnontia and consequently only little can be added to the infor- 

 mation fnruishecl by previous authors. It is greatly astonishing that iio new 

 species have come to light and that even some of the old ones, discovered by 

 Hillebrand could not again be located. The most common species of Dclissea 

 are D. subconlata and D. nndulata. The former has however become rarer; this 

 is due mainly to the fact that it grows at the lower elevations at the outskirts of 

 forests, which have become invaded by foreign planis, especially the Hilo grass 

 {Paspalnin conjugatmn) so destructive to Hawaiian vegetation. D. undulata 

 has been recorded from all of the islands of the group with the exception of 

 Oahu, Lanai and Kahoolawe. On Hawaii it attains its best development espe- 

 cially on the high central plateau in the forests of Mauna Loa and Hualalai. At 

 Pulehua, South Kona, the writer met with large numbers of this species some 

 reaching a height of thirty-five feet. It ranges from three thousand feet at 

 Puuwaawa to six thousand feet elevation on the slopes of Mauna Loa. The 

 beautiful little crowns on stems perfectly straight, are often hidden in the foliage 

 of the Koa {Acacia Kna) so that only tin- gray straight stems covered with leaf 

 scars can be seen. They are espec^ially numerous at the bottoms of craters and 

 volcanic cones. Looking down into one of these cones, one sees the tops of this 

 curious plant, like cabliage heads protruding over tlu' I'ini of the cone. It is 

 also found throughout ihe forest on the border of the great plain, but is espe- 

 cially common in the volcanic cones described above, for the single reason that 

 they are not accessilile to rattle. Asa Gray seems to have confused the two 

 plants more or less, for he considers I), undulata merely as a form of D. suhcor- 

 data. The latter is a .small branching shrub, while the former has an entirely 

 different habit as can be seen from the illustration. Dclissea rlnjlidospcnna is 

 only found on Kauai, especially in the drier woods of Waimea, Kealia and else- 

 where. Heller records it from the east side of Ilanapepe river in wet woods near 

 the source of the Wahiawa. Dclissea jiarvi/lora was discovered by llillelirand 

 on the Kohala range and in the woods of ]\Iauna Kea on Hawaii, the plant has not 

 been re-collected and nothing is known regarding its habit. The same must be 

 said of n. fallar from the woods of Hamakua and Hilo. 



The remaining species D. laciniata and D. sinuata occur on Oahu in the drier 

 regions, the former from Wailnpe Valley on the eastern end of the island and 

 the latter I'roiu the dry valley of ilakaleha on the western range. A variety of 

 D. siniiaia has been found on Lanai. There is no doubt that all these species 

 are closely related, but they are unquestionably decadent. They are dying out 

 fast as arr the forests which they once inhabited. The few species may be 

 looked npon as the remnant of what was once probably an extensive tribe. But 

 as they seem not to be iiartial to the Inmiid rainforests and as the forests of 



