264 UNIVERSITY OF COLORADO STUDIES 



Ipomoea coccinea 



34. Seedling, natural size. 



35. Epidermis of cotyledon. 



36. Vertical section of cotyledon. 



37. Vertical section of leaf. 



38. Diagram of cross section of cotyledon stalk. 



39. Diagram of cross section of leaf petiole. 



Cosmos bipinnatus 



40. Young seedling, three-fourths natural size. 



41. Older seedling, three-fourths natural size. 



42. Vertical section of cotyledon. 



43. Vertical section of leaf. 



44. Diagram of cross section of basal part of cotyledon. 



45. Diagram of cross section of basal part of leaf. 



All drawings were made by the author from his own preparations. The drawings 

 of epidermis and of vertical sections of leaves and cotyledons represent a magnification 

 of about two hundred and fifty diameters. 



