292 ON OKCniDS collected at TTTK ISLAXD of nOURBOX. 



Ilichnicrs figure (;)rcli. Maur., t. 5.), whieli shows neither ri'stellnin 

 nor stigma. 



r 



Curve of the peduncle and fall of the sepals and petnls — Tlie 

 last note relates to Phdjna tetraf/nnus, Rchb. f., in which the sepals 

 and petals i'all off soon after expansion, the pedicel becoming re- 

 curved, and by this movement detaching and drawing up the con- 

 Tolute bract. This trait is "well-known, having been remarked 

 on in the text accompanying t. 4412 of the Bot. Mag., but the point 

 not cleared up relates to the circumstances under which the action 

 takes phice, and principally as to whether it occurs before or after 

 fertilisation. If the former, the large and gaily-coloured sepals and 

 petals must be regarded as useless structures, and therefore liable 

 to elimination ; in fact, themselves affording an instance of tho 

 commencement of a curious type of elimination, viz., detachment 

 bodily of the full-grown parts immediately growth is finished, tho 

 supposition that tlie parts are full-grown being founded on obser- 

 vation of other species of the same genus. On the other hand, if, as 

 is more probable, the fall of sepals and petals takes place after 

 fertilisation, we have here another member to add to the already long 

 list of plants which cast away parts, no matter how useful before, 

 immediately on the accomplishment of the role of the latter. 



In conclusion, I have only to repeat the expression of the hope 

 that these and numerous similar points will receive elucidation at local 

 hands. 



Exi'LANATION OF TaB. 181. 



Fig'. 1. — Spur and base of the column and labellum of the male flower of 

 Eidophia scripta, Ldl., showins^ the two folds (/) at the bottom of the column, 

 and the two crests on the labellum [l). 



Fipr. 2. — Column of AiranUtus scsuftipcdalit, LdL (copied from the Bot. Mag., 

 t. 5113). 



Fig 3. — Column of Listroetachyn poli/stachim, Rchb. f. 



Fig. 4. — Column of An(/rcec»m aphi/llnm, Thouars, with labellum attached. 



Fig. 5. — Flower o£ Listrontac/ri/s J'cscaf una lift, S. Moore, from a drawing in 

 Herb. Ldl, 



Fig. 6. — Column of Cynorchin fnstigiafo, Tho\iars. 



Fig. 7. — Column of C. pin-pxr/zsni/s, Thouars. 



Figs. 4 and 5 several times magnified ; the rest about natural sizn. 



In all figures a marks anther-case, c coluum, r rostellum, *■ stiguia, g gland, 

 n ' arms of the anther, and sp spur. 



OX THE ORCHIDS COLLECTED AT THE ISLAND OF 

 BOURBOX, DURING THE TRANSIT OF VENUS EXPE- 

 DITION, BY DR. I. B. BALFOUR. 



Br S. Lk M. Moore, F.L.S. 



A FORTNionT's stay at Bourbon enabled Dr. Balfour to obtain good 

 gatherings of Orchids. In one or two cases he has brought back 

 Thouarsian types which have probably not been seen since their first 

 publication, as well as some very rare and some new species. The 

 list is as follows. 



