Apr.-Sept., 191 5 IllustratioTis 



XIII 



Page 

 Plate LIII. Fig. i. — Clematis jackmanni: A vine free from leaf -spot that has 



been girdled by Ascochyta cleinatidina in the region of the previous year's 



stub a. Fig. 2. — Clematis jackmanni: Plant from which the diseased stub 



a was cut away without removing the discolored tissue 342 



Plate LIV. Fig. i. — Ascochyta cleinatidina: Photomicrograph of a pycnidium 



from stained section of a leaf of Clematis paniculata. Fig. 2. — Ascochyta 



clematidina: Culture growing on agar to which Ivory soap at the rate of i 



pound to 15 gallons of water was added, showing the oily film about the 



margin of the cultiu-e in which the crystals of stearic acid are found 342 



Wallrothiella Arceuthobii 



Plate LV. Fig. i. — Razoumofskya douglasii on Pseudotsuga taxifolia, infected 

 with Wallrothiella arceuthobii. Fig. 2. — R. douglasii, var. abietina, on Abies 

 grandis, infected with W. arceuthobii. Fig. 3. — R. douglasii, var. abietina, 

 on Abies lasiocarpa, infected with W. arceuthobii. Fig. 4. — R. douglasii, var. 

 microcarpa, on Picea engelmanni, infected with W. arceuthobii. Fig. 5. — 

 Left and right figures showing infection of R. americana with W. arceuthobii 

 by infected plants of R. douglasii. The middle figure shows infection of 

 R. americana by spraying upon the plants a mixttue containing spores of 

 W. arceuthobii 378 



Plate LVI. Fig. i. — Enlargement of the normal fruits of Razoumofskya ameri- 

 cana shown in Plate LV, figure 5. Fig. 2. — Enlargement of the diseased 

 fruits of R. americana infected with Wallrothiella arceuthobii shown in Plate 

 LV, figure 5 378 



Tensile Strength and Elasticity of Wool 



Plate LVII. Fig. i. — Diagrammatic drawing of the fiber-testing machine of 

 the Philadelphia Textile School. "/, Jaws with screw clamps for holding 

 the fiber; the lower jaw may be raised or lowered; R, sliding rod working 

 on a rack and pinion; this takes the place of weights; G, wheel graduated 

 on its face in decigrams, moving on the same axis as the pinion for sliding 

 the weight; T, thumbscrew for turning the small shaft working the pinion 

 at P; W, coimterbalancing weight for regulating the zero point of the ma- 

 chine; S, scale for reading the sketch of the fiber. " (From Matthews 's The 

 Textile Fibres.) Fig. 2. — Fiber-testing machine removed from its case. 

 Fig. 3 . — Diagram showing the arrangement of the wool -testing apparatus at 

 the Montana Agriculttual Experiment Station 390 



Influence of Hybridization and Cross-Pollination on the Water 

 Requirement op Plants 



Plate LVIII. First-generation hybrids and parents used in 1912 experiments. 

 Fig. I. — Laguna com, grown July 2 to September 26, 1912. Fig. 2. — 

 Esperanza corn, grown June 12 to September 26, 1912. Fig. 3. — China 

 com, grown June 12 to September 26, 1912. Fig. 4. — Hybrid ChinaX 

 Laguna com, grown June 12 to September 26, 1912. Fig. 5. — Hybrid 

 ChinaX Esperanza com, grown June 12 to September 26, 1912 403 



Further Studies of the Embryology op Toxoptera Graminum 



Plate LIX. Toxoptera graminum: Fig. 1-3. — Sagittal sections. Embryo start- 

 ing revolution. Fig. 4-6. — Sagittal sections. Embryo making revolution . 404 



Plate LX. Toxoptera graminum: Fig. 1-3. — Sagittal sections. Revolution is 

 almost complete and shows fate of the polar organ, p.o. Fig. 4-6. — Sagittal 

 sections, d. o.. Dorsal organ 404 



