516 MINNESOTA BOTANICAL STUDIES. 



EXPLANATION OF PLATES. 



PLATE XXVIII. 



Isopyrum biternatum with flowers and seed capsules. 



PLATE XXIX. 



Anatomy of Isopyrum biternatum. 

 Fig. 1. Cross section of tuber. X 100. 



a. Cortex. 



b. Endodermis. 



c. Meristematic arch. 



d d. Rays of meristematic tissue. 

 e e. Secondary hadrome. 

 //. Primary hadrome. 

 Fig. 2. Parenchyma cell showing leucoplasts containing starch grains- 



at time of flowering. X 450. 

 Fig. 3. Parenchyma cell with nucleus covered by layer of starch grains 



at time of maturity of seeds. X 450. 

 Fig. 4. Parenchyma cell taken from tuber grown in plant house during 



December. Treated with absolute alcohol for 100 days. X450. 

 Fig. 5. Parenchyma cell taken from tuber in February. Freshly treated 



with absolute alcohol. X 450. 

 Fig. 6. Cross section of root 3 mm. from tip. X 700. 



c. Endodermis. 



b. Primary hadrome. 



a. Group of cells from whic h secondary hadrome arises. 

 Fig. 7. Plant 4 months old. 



a. Tubers, £ natural size. 

 Fig. 8. Surface section of tuber. X 450. 



a. Oil drops. 



b. Hypha. 



Fig. 9. Root thickened into tuber. X 10. 

 Fig. 10. Seedling. 



a. Cotyledon. X 12. 



c. First foliage leaf. 



b. Second foliage leaf. 



d. Third foliage leaf. 



Fig. 11. Diagram showing disposition of tissues in branch of tuber. 



c. Primary hadrome. 

 b. Secondary hadrome. 

 a. Endodermis. 



