DENDROBIUM. 85 



ance among the numerous importations of species of Dendrobium 

 that have of late years filled the orchid houses of Europe to 

 overflowing. But so it is — with the solitary exception of D. crassi- 

 nodi-Wardianum, an undoubted natural hybrid, we know of no 

 other well-attested instance, although from time to time, hypotheses 

 have been hazarded respecting the hybrid origin of some of the 

 Dendrobes in cultivation, but which, since their first appearance, 

 have been generally accepted as good species. So long ago as 

 1874, Professor Reichenbach (Xen. Orch. II. p. 209 — 10), when point- 

 ing out the difficulty attending the identification of certain Den- 

 drobes from their flowers only — a difficulty greatly heightened when 

 the flowers come to hand in a dried state, instancing D. Boxalli, 

 D. crystallinum, D. Findlayanum, and D. gratiosissimum — suggested 

 the possibility of at least two of these being natural hybrids, 

 viz., D. Boxalli between D. gratiosissimum and D. crassinode, and 

 D. Findlayanum between D. Aphrodite and I), gratiosissimum.* But 

 this theory has thus far failed to find acceptance, the chief fact 

 that militates against it being the quantity in which both have been 

 imported, a fact that affords sufficient ground for giving them specific 

 rank, apart from some structural peculiarities that cannot be recon- 

 ciled with their supposed hybrid origin. D. rhodopterygium has been 

 adduced as another instance of a natural hybrid, the supposed 

 parents being D. Pierardi and D. Parishii, but here again, although 

 the probability is much stronger than in the preceding cases, fur- 

 ther evidence appears to be undoubtedly wanting to establish the 

 hypothesis. 



Into the causes of this paucity of natural hybrids in this genus 

 it is not our present purpose to inquire; we simply note the 

 fact as one among the many unsolved mysteries of orchid life. 



Even muling among Dendrobes by hand is, comparatively speak- 

 ing, still in its infancy, large as is the field offered by the genus 

 for the operations of the hybridist. Dominy raised the hybrid that 

 bears his name many years ago at the Exeter Nursery; he was 

 followed at intervals by various operators, the most successful of 

 whom is Seden, who, by widening the area of his operations, has 



* In his own words, " Es ist sehr wahrscheinlick dass Bastardinmgen vorkommen, zu denen 

 vielleicht sogar Dendrobium Aphrodite, D. Bensonioz, und D. Parishii ihre contingente liefern. 

 Wer konnte sich dem Verdachte entziehen dass aus D. gratiosissimum und crassinode, das 

 Boxalli werde ? Und ist vielleicht D. Findlayanum ein Product des D. Aphrodite und 



gratiosissimum. 



