196 VANDEiE. Chap. VIL 



aud are extended symmetrically. lu C. saccatum the 

 left arm is bowed and held in front, as in C. triden- 

 tatum, but rather lower down ; whilst the right arm 

 hangs downwards paralysed, with the hand turned a 

 little outwards. In every case notice will be given in 

 an admirable manner, when an insect visits the label- 

 lum, and the time has arrived for the ejection of the 

 pollinium, so that it may be transported to the female 

 plant. 



Catasetum tridentatum is interesting under another 

 point of view. Botanists were astonished when Sir K. 

 Schomburgk* stated that he had seen three forms, 

 believed to constitute three distinct genera, namely, 

 Catasetum tridentatum, Monachanthus viridis, and 

 Myanthus harhatus, all growing on the same plant. 

 Lindley remarked! that "such cases shake to the 

 foundation all our ideas of the stability of genera and 

 species." Sir E. Schomburgk afBrms that he has seen 

 hundreds of plants of G. tridentatum in Essequibo with- 

 out ever finding one specimen with seeds ; | whereas 



* 'Traiisaclions of theLinncan Bristol. Lastly Dean Herbert 



Soc.' vol. xvii. p. 522. Another informed me many years ago tliat 



account by Dr. Lindley appeared Catasetum luridum flowered and 



in file 'Botanical Begister,' fol. kept true for nine years in the 



1951, of a distinct species of My- Botanic Garden at York ; it then 



anthus and Monacbantbns appear- threw up a scape of a Myantlms, 



ing on the same scape : he alludes which as we shall pr. sently tee U 



also to other cases. 8ome of the an beimapbrodite, intermediate in 



flowers in these cases were in an in- form between the male and ft-male. 



termediate condition, which is not M. Duchartro has given a full his- 



snrprising, seeing that in dioecious torical account of the appearance 



plants we sometimes have a partial of these forms on the same plant, 



resumption of the characters of in 'Bull, de la Soc. Bot. de 



both sexes. Mr. K<dgers of River- France,' vol ix. 1862, p. lis. 



hill informs me tliat he import, d t The 'Vegetable Kingdom,' 



from Denierara a Myanthus, and 1853, p. 178. 



that when it flowered a second % Brongniart states (' Bull, de 



time it was metamorphosed into la Soc. But. de France,' toin. ii. 



a Catasetum. Dr. Carpenter 1 855, p. 20) that M. Neumann, a 



('Comparative Physiology,' 4th skilful fertiliser of Orchids, could 



edit. p. 633) alludes to an ana- never succeed in fertilising Cata- 



iogous case which occurred at setum. 



