16 



ASPASIA EPIDENDROIDES. 



Western Columbia ; and is one of the plants collected by Mr. Cuming in South 

 America. 



In our first number we made a few observations on the singular habits and 

 appearance of orchidaceous plants ; and presuming that many of our readers may 

 be unacquainted with their peculiarities, we shall take this opportunity of offering 

 a few remarks on the anomalous structure of their flowers; a subject highly 

 curious in itself, and (in a botanical point of view) equally important. It is 

 curious as presenting a remarkable deviation from the usual structure of this 

 part of plants ; and important, as affording the most convenient means for their 

 classification. Orchidaceous plants have not a certain number of stamens disposed 

 around one or more pistils, like other flowering plants ; but are furnished, instead 

 of them, with a central fleshy body, called the column, round which the sepals and 

 petals are arranged. This fleshy body (which varies greatly in length in different 

 genera) is considered to consist of three stamens and a style in a state of firm 

 cohesion. The stigma, instead of forming the extremity of the style as in other 

 flowers, is a moist cavity situated in front of the column, immediately below the 

 summit. At the apex of the column is placed a solitary anther, the lateral 

 stamens being abortive, or imperfectly developed. A curious deviation from this 

 arrangement of parts occurs in Cypripedium, which has the lateral stamens perfect, 

 and the central one abortive. In a few of the genera the anther is persistent, but 

 in by far the greater number it is deciduous. On removing the anther we discover 

 the pollen-masses, which are subject to various modifications of structure. They 

 have accordingly been divided by Dr. Lindley (whose intimate acquaintance with 

 these extraordinary plants is well known) into several distinct tribes, in a work 

 devoted expressly to their description.* In our present plant the pollen-masses 

 are connected with a gland, by means of a transparent elastic strap, called the 

 caudkula. We shall continue our remarks upon this singular order of plants in 

 our next number. 



Fig. 1, anterior view of the pollen-masses and appendages magnified : a the 

 pollinia ; b the caudicula ; c the gland. Fig. 2, posterior view of same ; 3, the 

 column, showing the claw of the labellum united with it as far as the middle ; 

 and the lamina spreading horizontally and forming a right angle. 



* The Genera and Species of Orchid. Plants, by John Lindley, Ph.D., F.R.S., &c, &c. 



