Studies of Selected Spermatophytes. 22 1 



points of dissimilarity which cause these two Ariscemas to 

 be classed as different species. 



Erythronium z\h\A.M.rD.. — Do^ s-tooth Violet. 



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 1 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 bulbs of Erythroniuvi Americmium and Erythronium 

 albidmn are each successive year formed deeper in the 

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



