Cabsk. — On Panax arboreuin. 361 



In some of the specimens I noticed the tree fern was 

 perfectly healthy and in a robust state ; in others it was 

 apparently suffering from the close embraces of its too 

 vigorous foster-child, as was shown by the poorly developed 

 fronds. In two cases I saw the enclosed tree ferns had 

 succumbed. In one of these instances the lower part of 

 the caudex was entirely surrounded by the coalescing "root- 

 stems " of the Panax, except at one point, where about 6 in. 

 of the caudex was visible. Rising above the point where I 

 judged the germination of the Panax to have taken place was 

 seen about 2 ft. of caudex half imbedded in the trunk of the 

 Panax. What remained of the caudex was dry and brittle, 

 having apparently been dead for many years. Judging from 

 the remains, I concluded that it had been a Dicksonia squar- 

 rosa, which fern is plentiful in the immediate vicinity. In 

 the second case the circumstances are very similar, save that 

 the enveloping and fatal " root-stems " have formed a ring 

 about 3 ft. above the ground and have then coalesced, forming 

 a concave trunk containing the compressed remains of the 

 fern, apparently also a Dicksonia. In these two cases no 

 " Crowner's quest " appears necessary as to the cause of 

 death. The self-evident verdict must be "Death from con- 

 striction." But in another case further inquiry is called for. 

 The facts are as follow : A Panax arboreum has germinated 

 on a Cyathea dealbata, has grown and flourished until it 

 became a tree 20ft. high, its coalescing "root-stems" envelop- 

 ing a considerable portion of the stem of its foster-parent. 

 The strange thing in this case is that, while the tree fern is 

 in a state of luxuriant growth, producing a fine crown of 

 fronds, the Panax is dead and dry. 



From my observations I have arrived at the conclusion 

 that Cyathea dealbata probably in many cases suffers in 

 health from the embraces of Panax arboreum, but rarely, if 

 ever, succumbs ; but that Dicksonia. squarrosa, being usually 

 less robust, is more apt to find these embraces fatal. 



Whether this peculiar habit of Panax arboreum shows its 

 natural affinity with the ivy-piant (Hedera), as suggested by 

 Mr. Colenso, or no, I leave to more advanced students of 

 nature to decide ; but it seems to me we might say the 

 same of the rata (Metrosideros robusta), which usually begins 

 life as an epiphyte in the clefts of the upper branches of 

 forest trees, and frequently serves its. foster-parent in a 

 manner similar to that described above in the case of 

 Dicksonia squarrosa. 



Subjoined are a few notes of measurements in some of the 

 cases referred to : — 



No. 1. Cyathea dealbata, 15 ft. high ; Panax arboreum, 

 20 ft. high. Point of germination, 6 ft. above ground. 



