304 



IOWA ACADEMY OF SCIENCE Vol. XXV, 191S 



sliirhtly curved. Cell-wall tiiin, contents granular. Trichomes 

 occur singly, very numerous. 



Carya alha (L) K. Koch. Mocker nut. Clemson College. De- 

 ceniher 7. 1017. Wintered in tlie gi-eeniiouse. germinated ^Mareli 



Fie:. 51 Fig. 52 



Fig^. 51. — Trichomes on leaf of Carya hiciniosa seedling, showing- glandu- 

 lar tip of serration. Drawn by C. M. King-. 



Fig. 52. — Trichomes of Carya alba from stem and leaves of seedlirg. 

 a, glandular trichome. Drawn by C. M. King. 



28. 1918. Germination hypogaeous ; first leaves scalelike, alter- 

 nate. Stem resinous and slightly pubescent, globules yellow. 

 Scales five. First, second and third leaflets somewhat pubescent 

 and covered with resinous srlobules on lioth surfaces. Petiole 



Fig. 53. — 'Germination of hickory nut (Carya alha), various stages: early 

 leaves of three leaflets, penninerved. Pliotogrphead by Photo. Section, F. 

 K. Colburn. 



slightly pubescent, also with resinous globules. Stalks of leaf- 

 let slightly pubescent and resinous. Margins serrate, tenninal 

 leaf serrate only beyond the middle. Trichomes occur singly, 

 slin-htly curved, base enlarged ; 1-eelled cell wall of medium thick- 



