AmphicartHza mqnoica. 335 



tion upon the plant. The aerial cleistogamic form occurs 

 persistently and for a long period. 



As for the underground flowers, from the middle of June 

 until October, unceasingly Amphicarpcea is adding to the 

 number. No average environment seems to prevent their 

 production : but there is marked difference in the size and 

 number of legumes produced. 



Among the Oxalidacea: the special underground shoots 

 do not develop until the summer months are far advanced. 



Epiphegus Virginiana shows a similar behavior to Amphi- 

 carpa-a. During the summer of 1896 Dr. Macfarlane ob- 

 served at Woods Hole Polygala polygamy which grows 

 there abundantly. Early in the summer he found this 

 plant to produce subterranean flowers, many of which ripen 

 fruit before the aerial flowers have opened. After the 

 purple flowers have almost ceased blooming, colorless 

 flowers appear above ground, upon elongated shoots which 

 develop below those bearing purple flowers. A study of 

 these is now being made by Mr. C. H. Shaw. 



Is the behavior of Amphicarpcea in winter not due to 

 absence of intensity in the sun's rays? High temperature 

 and abundant light and moisture were provided, still plants 

 in the green-house from January to end of April showed 

 no purple blossoms. Yet others placed in the same part of 

 the green-house in May were covered with these flowers 

 in August. 



Linnaeus relates a similar experience with plants taken 

 to the Gardens of Upsal 5 - 6 ; they produced inconspicuous 

 flowers only. Gray, 9 too, reports similar experiences with 

 certain plants in the Cambridge Garden. Insufficient tem- 

 perature might be adduced as a cause for this non-produc- 

 tion of colored blooms; but from my experience with 

 Amphicarpcea the light intensity is without doubt an im- 

 portant factor. 



