Jan. 6-Mar. 31, 1919 IllustratiOflS XI 



Life-History Observations on Four Recently Described Parasites 

 OF Bruchophagus funebris 



Page 



Fig. I . Liodontomerus perplexus: Larva 168 



2 . Liodontomerus perplexus: Pupa 168 



3. Liodontomerus sccundus: Larva 170 



4. Liodontomerus secundus: Pupa 170 



5. Eutelus bruchophagi: Larva 171 



6. Eutelus bruchophagi: Pupa 171 



7. Trim,erom.icrus maculatus: Larva 173 



8. Trimeromicrus m.aculaius: Pupa 173 



Apple-Scald 



Fig. I. Graphs showing the effect of maturity upon susceptibility of Grimes 



apples to scald 197 



2. Graphs showing the relative susceptibility to scald of eastern and 



western Grimes apples 198 



3. Graphs showing the effects of temperature on apple-scald at the end 



of 4, 6, 7, 9, 13, and 16 weeks 199 



4. Graphs showing the effects of temperature on apple-scald at the end of 2 , 



3, 4, 5, 7, 12, and 16 weeks 200 



5. Graphs showing the effects of temperature on apple-scald at the end of 



2,3,4, 5, 9, and II weeks 20a 



6. Graphs shomng the effect of temperature on apple-scald at the end of 5, 



7,9, II, 13, 16, and 19 weeks 203 



7. Graphs showing the effect of temperature on apple-scald at the end of 7 , 



10, 12, and 18 weeks 204 



8. Graphs showing the effect of temperature on apple-scald at the end of 



12 , 14, 20, and 26 weeks 205 



9. Graphs showing the effect of temperature on apple-scald at the end of 



8, 12, 16, and 20 weeks 205 



10. Graphs showing the effect of temperature on apple-scald at the end of 



8, 12 , and 16 weeks 209 



11. Graphs showing the relation of carbon dioxid to apple-scald production . 2 10 



Two Species of Pegomyia Mining the Leaves of Dock 



Fig. 1. a, phar^'ngeal skeleton of first instar, Pegomyia calpytrata Zett; B, phar- 

 yngeal skeleton of second instar, P. calyptrata; C, mandibular scle- 

 rite of second instar, P. calyptrata; D, pharj'ngeal skeleton of third 

 instar, P. calyptrata; E, phar}-ngeal skeleton of first instar, P. affinis 

 Stein; F, mandibular sclerite of first instar, P. affinis; G, phary-ngeal 

 skeleton of second instar, P . affinis; H, pharyngeal skeleton of third 

 instar, P. affinis 233 



A Field Study of the Influence of Organic Matter uton the Water- 

 Holding Capacity of a Silt-Loam Soil 



Fig. I. Diagram showing arrangement of plots and crops on field J, University 

 Farm, St. Paul, Minn. A is the original plan adhered to from 1893 to 

 1914, while B shows the cropping plan in 1915. C shows the arrange- 

 ment of the samples taken for the two composites from a plot 265 



2. Diagram showing the amount and distribution of the rainfall at Univer- 

 sity Farm, St. Paul, Minn., during part of the season of 191 5. The 

 dates of sampling are indicated by asterisks 269 



