VI Journal of Agricultural Research voi.xix 



Page 



6. Teosinte-maize hybrid: A. — F, plant No. 31, showing compact growth 



characteristic of many of the plants. B. — F2 plant No. 113, showing 

 stiff, erect leaves. C. — Fj plant, grown at Lanham, Md 38 



7. Teoshite-maize hybrid: Pistillate inflorescences of the Fj plant shown in 



plant 6, C 38 



Banana Root-Borer 



Text Figure 



I. Cosmopolites sordidus: Section of sheath with egg m ji7m in compartment . 44 



Plates 



8. Banana root-borer (Cosmopolites sordidiis): Adult 46 



9. Egg and larva of banana root-borer: A. — Egg. B. — Larva, side view. 



C. — Head of larva, dorsal view. D. — Head of larva, face view. E. — 

 Head of larva, side view. F. — Dorsal view of seventh, eighth, and 

 ninth abdominal segments. G. — Posterior view of segments 7 to 10. . . . 46 



10. Pupa and adult of banana root-borer: A. — Ventral view of pupa. B. — 



Lateral view of head and thorax of pupa. C. — Dorsal view of pupa ... . 46 



11. A. — Yoimg, healthy banana plant bulb with lateral roots. B. — Young 



banana plant cut into, showing work of the larvae of the banana root- 

 borer 46 



Further Studies on the Influence op Humidity upon the Strength 

 AND Elasticity of Wool Fiber 



Text Figures 



1. Graphs showing the effect of humidity upon the breaking strength of wool 



fiber 56 



2. Graphs showing the effect of humidity upon the elasticity of wool fiber. . . 57 



3. Graphs showing the relation between the diameter and the tensile strength 



of wool fiber 60 



4. Graphs showing the effect of humidity upon the breaking strength and 



elasticity of wool fiber 62 



Composition and Density of the Native Vegetation in the Vicinity op 

 THE Northern Great Plains Field Station 



Text Figures 



1. Diagram of grass mat: A, from side; B, from above, a, Basal cover; b, 



foliage cover 68 



2. Meter quadrat in 30-acre pasture mapped in detail in 1915 6g 



Plates 



12. General view of native vegetation near Mandan, N. Dak., showing com- 



position and density 72 



13. A. — View across area of Andropogon furcatus. B. — Close view of Aristida 



longiseta bunches 72 



14. A. — Close view, from above, of meter quadrat in 30-acre pasture. B. — 



Meter quadrat in 30-acre pasture 72 



