Prof. Link on the Structure of the Orchidacea?. 37 



Lindley calls the corolla. Yet the labellum never stands in a 

 circle with the two leaflets of this corolla, but always with the 

 column (columna,gymnostemium), in which stamens and style are 

 blended together ; indeed in most cases it is itself confluent with 

 this. Lindley himself mentions this, and adds, that in some 

 species of the Cape genus Pterygodium the labellum proceeds 

 from the apex of the column. If in these cases we should assume 

 an external adherence of the labellum to the column, which how- 

 ever in some, especially in Scaphy glottis, could not be supposed, 

 on account of the insensible transition, then the base of it 

 ought to stand in a circle with the leaflets of the corolla, which 

 never happens. Even in the cases where the labellum appears 

 quite separate from the column, in Cattleya, many Maxillarice, 

 and also in our indigenous species of Orchidacese, there is always 

 a confluence of the base with the column, above the leaflets of 

 the corolla. It does not admit of doubt, that the prevalence of 

 the number three in the class of Monocotyledons gave rise to the 

 idea that the labellum belongs to the corolla. But facts are pre- 

 ferable to opinions. 



Moreover if we examine the upper side of the column in the 

 indigenous Orchidacese, e. g. in Orchis itself, we see a part, broad 

 below and running up into a point above, embracing the two 

 anther-cells. This is evidently a connecticulum ; that is, the upper 

 expanded part of the stamen, which bears the two chambers of 

 the anther. If we make a transverse section, first through the 

 upper part of the column, where the excavation of the stigma is 

 still shallow, we see a large vascular bundle on the outer side ; 

 further in, another smaller ; but not a trace of a vascular bundle 

 on either side. Lower down, where the cavity of the stigma is 

 much expanded, we find three vascular bundles, but in a straight 

 line from the upper surface to the cavity of the stigma. The 

 three vascular bundles cannot therefore denote three stamens, 

 but belong only to the one stamen and the style, in which the 

 vascular bundles usually surround the stigmatic canal on two or 

 three sides. The lateral wings, which are here very thick and 

 arched, certainly have delicate spiral vessels, but horizontal in 

 direction, while if they belonged to stamens they ought to run 

 vertically from below upward. 



When we examine, further, the column of one of the Vandece 

 or Epidendrea, we find the operculum of the anther, which like- 

 wise represents a connecticulum, distinctly surrounded by another 

 part, which is very often furnished with various appendices and 

 wings, clearly belonging to the external envelope of the column. 

 I have given an enlarged transverse section in my Anatomical 

 Plates, pi. 19 & 20, from Epidendrum elongatum. Here the stig- 

 matic canal is surrounded by a quantity of vascular bundles, 



