ORCHIDACEiE 



tubers are provided with endotropic fungi (mycorrhiza), although 

 the sections I have examined indicate that the fungal elements 

 are restricted and are usually present only in the basal half, that 

 is, near the end by which the tuber was originally attached to the 

 stolon. 



The flowers of Triphora trianthophora differ fundamentally 

 from those of other New England orchids in their brief duration. 

 The flowers seem to fade rapidly shortly after the sepals and 

 petals expand, and it is very evident that floral perfection is a 

 matter of hours rather than of days. The labellum is a very beau- 

 tiful object, the brilliant green raised nerves, that traverse the 

 middle longitudinally, forming a striking contrast with the whit- 

 ish disc which seems to be composed of myriads of tiny crystals 

 in piles of unequal density and depth. Shortly after anthesis the 

 margin of the middle lobe becomes strongly involute, an indi- 

 cation of the passing of floral perfection. The lip of T. triantho- 

 phora is unlike the lip of its near allies, Pogonia and Isotria, and 

 is devoid of calli or glands at the extreme base. In the flower the 

 gynostemium or column is the structure of greatest interest, not 

 only because it exhibits weighty characters for purposes of clas- 

 sification, but because it is very unlike the gynostemium of Po- 

 gonia, Isotria and Cleistes. At base it is semiterete; near the mid- 

 dle it becomes laterally dilated. The clinandrium has a strongly 

 deflexed margin and is flat or slightly rounded above. (Cf Plate 

 102, figs. 4-6.) The most remarkable structure, however, is ex- 

 hibited by the anther. This is subcylindrical, blunt at the apex 

 and attached to the body of the column by an unjointed, rigid, 

 semiterete base. From the white body of the anther the flanges 

 of the cells that contain the pollinia extend forward. These are 

 of a rich red-purple color, forming a strong contrast with adjoin- 

 ing tissues and making the structure comparable, when seen 



[11 ] 



