Chap. III. 



TTEEOSTYLIS LONGIFOLIA. 



91 



in tbe proper manner.* I will mention only two pecn- 

 liarities in the structure of the flowers : the anterior 

 part of the pollen-masses is semi-waxy and the posterior 

 part somewhat friable ; the grains are not cemented 

 together into compound grains, and the single grains 

 are not united by fine elastic threads but by viscid 

 matter ; this matter would aid in causing the pollen 

 to adhere to an insect, but I should have thought that 

 such aid was superfluous, as the viscid rostellum is 

 well developed. The other peculiarity is that the 

 labellum, in front of the stigma, and some way beneath 

 it, is furnished with a stiff hinged brush, formed of a 

 series of combs one over the other, which point down- 

 wards. This structure w^ould allow an insect to crawd 

 easily into a flower, but would compel it whilst re- 

 treating to press close against the column ; and in 

 doing so it would remove the pollen-masses, leaving 

 them on the stigma of the next flower which was 

 visited. 



The genus Sobralia is allied to Yanilla, and Mr. 

 Cavendish Browne informs me that he saw a large 

 humble-bee enter a flower of S. macrantha in his 

 hothouse, and w^hen it crawded out it had the two 

 large pollen-masses firmly fixed to its back, nearer to 

 the tail than to the head. The bee then looked about, 

 and seeino- no other flower re-entered the same one of 



* For Bourbon fee ' Bui. Soc. 

 Bot. de France,' torn. i. 1854, p. 

 2S);i. For Tahiti see H. A. Tilley, 

 ' Japan, the Amour, &c.,' 1861, p. 

 'Mb. For the East Indies see 

 Morren in ' Annals and 3Mag. of 

 Nat. Hist.' 1839, vol. iii. p. (J. I 

 may give an analouous but more 

 .-•trikiug case from Mr Fitzgerald, 

 who says "that Sarcochilus jiar- 

 riflorus (one of the YatidcKi) pro- 

 tluco8 cap.sules not nnlVeuueiitly 



in the Blue Mountains of New 

 South Wales ; removed from 

 thence to Sydney, a number of 

 plants, though flowering well, have 

 not borne any seed if left to them- 

 selves, though invariably fertile 

 when the pollen-massea were re- 

 moved and ]di\c{don the stigma." 

 Yet the Blue Jlountaitis are lets 

 than one hundred miles distani 

 from Sydney. 



