XX Journal of Agricultural Research voi. vi 



Citrus Canker 



Page 

 Fig. I. Diagrammatic representation of young open type of Citrus canker of 



half the diameter of the one shown in figure 2. pp, Palisade paren- 

 chyma; ue, upper epidermis; le, lower epidermis; d, diseased tis- 

 sues; a, air space arising from tensions due to the enlargement of 



cells and disintegration of tissues 72 



2. Diagrammatic representation of canker on old Citrus leaf; pp, Palisade 

 parenchyma; ue, upper epidermis; le, lower epidermis; p, pycnidium 

 of Phonia socia; d, diseased tissues; a, air space arising from tensions 



due to the enlargement of cells and disintegration of tissues 73 



Pseudomonas citri: a. Stained with carbol fuchsin; b, stained with 

 Williams's flagellar stain (adapted from Hasse); c, stained with 

 anilin gentian violet 76 



4. Early stage of Citrus canker in cross section on a young leaf of seedling 



grapefruit 80 



5. Pseudomonas citri: (a). In the mesophyll tissue and (6) in the palisade 



parenchyma 81 



6. Drawing of a stained section of a natural canker on grapefruit 82 



7. Cross section in outline of a spongy canker on the rind of a fruit of 



Citrus decumana, showing ruptured epidermis and hypertrophy of 



the rind tissues, the cells of which are loosely attached 83 



8. a. Cross section of a pycnidium of Phoma socia from a grapefruit leaf. 



b, Germination of conidia of Phoma socia after 24 hours in water, c, 

 Mycelium of this fungus in old cultures 86 



Determination of Stearic Acid in Butter Fat 



Fig. I. Exterior of constant-temperature crj'^stallization tank 104 



2. Interior of constant-temperature crystallization tank 105 



LiPE History and Habits of Two New Nematodes Parasitic on Insects 



Fig. I. Diplogaster labiata: A, Mating; B, mature female reared in water cul- 

 ture, a, lip region, 6, esophagus, c, median bulb, d, cardiac bulb, 



c, intestine,/, ovaries, g, egg, h, genital pore, i, rectum, k, anus; 

 C mature male reared in water culture, a, lip region, b, esophagus, 

 c, median bulb, d, cardiac bulb, e, intestine, k, anus, m,, spicula; 

 D, at time of hatching; E, female during process of molting; F, dead 

 female with yoimg nematode which hatched within her body 116 



2. A~H, Diplogaster labiata: Developmertt of the egg; /, Diplogaster 



aerivora: mature male reared in moist soil; /, Diplogaster aerivora: 

 mature male reared in water culture, a, lip region, b, esophagus, c, 

 median bulb, d, cardiac bulb, e, intestine, k, anus, m, spicula; K, 

 Diplogaster aerivora: dead female with yotmg which hatched within 

 her body; L, Diplogaster aerivora: mating 117 



3. Diplogaster aerivora: A, Form found in termite; B, at time of hatch- 



ing; C, female reared in water culture, not quite mature, a, lip 

 region, b, esophagus, c, median bulb, d, cardiac bulb, e, intestine, 

 /, ovaries, h, genital pore, i, rectum, k, anus; D, mature female 

 reared in moist soil; E, mature female reared in water culture; 

 F-M, development of the egg 122 



Effect of Pasteurization on Mold Spores 



Fig. I. Curi'e of the number of species of molds siu^iving pasteurization of 



milk for 30 minutes at a series of temperatures 157 



2. Curve of the number of species of molds surviving flash pasteurization 



at a series of temperatiu^es 160 



