Studies of Selected Spermatophytes. 221 



points of dissimilarity which cause these two Arisamas to 

 be classed as different species. 



Erythronium albidum (or other species). 



Make a diagram of the flower, following the general 

 directions on pages 148-151. Make a drawing to show the 

 habit of the entire plant, including the bulb and roots. 

 How deep does the bulb lie in the ground ? How close to 

 the ground do the leaves originate ? What is the light 

 relation of the leaves ? Do both sides of the leaf receive 

 the light energy about equally ? How early in the spring 

 do the leaves appear ? What advantages do you see in 

 the very early development of this plant ? In its chosen 

 habitat is it at a disadvantage later in the season ? Is it 

 apt to be much shaded by other plants ? Make observa- 

 tions in the field to determine how leaves and flowers come 

 through the ground. Is the flower upright or in a nodding 

 position when it first appears ? Does the flower open as 

 soon as it appears ? Of what use is the nodding position 

 of the flower ? Do insects visit the flowers, and if so see 

 whether they appear to be in quest of pollen or nectar. 

 Can you find nectar and nectaries ? In what ways are 

 nectar and pollen protected from the rain ? At what time 

 in the development of the flower do the anthers dehisce ? 

 Are the flowers at all proterogynous or proterandrous ? 

 Do the anthers touch the stigmas, or could self pollen fall 

 upon them ? 



Note the further course of the plant through the season. 

 Do many seeds mature in the capsule ? How are the seeds 

 scattered ? When do the leaves ripen and wither away ? 



The buds of Erythronium Americanum and Erythronium 

 albidum are each successive year formed deeper in the 

 ground by means of an offshoot which bears a new bulb at 



