106 
MEASLES, 84 
Mechanical contamination, § 
Mechanical transmission, 25 
Metal shadowing, 66 
Microtactoids, 50 
Mites, 20, 28 
Mosaic diseases, 32 
Myzus ornatus, 23 
Myzus persicae, 23 
NEUTRALIZATION (of viruses), 72 
Newcastle disease, 9, 86 
Nicotine fumigation, 91 
Non-persistent viruses, 26, 27 
Nucleic acid, $1, 53 
PARACRINELE, 4, 17 
Pediculus (louse), 25, 28, 87 
Pepsin, 73 
Persistent viruses, 26, 27 
Phaedon cochleariae, 20 
Phyllotreta spp., 20 
Plant breeding, 93 
Poliomyelitis, 26, 89 
Polyhedral diseases, 6, 8, 10, 17, 38, 39, 86 
Polyhedral viruses, purification of, 47 
Potato ‘“‘curl,”’ 1 
Potato virus X, 6, 18, 22, $8, 59, 60, 69, 75, 
78, 93 
Potato virus Y, 22 
Potato yellow dwarf, 22 
Prairie chicken, 88 
Precipitin reaction, 72 
Protective inoculation, 94 
Pseudorabies, 13 
“Q” fever, 20, 68, 89 
Quarantine, 87 
Rassit papilloma virus, purification of, 
46, 56 
Radiation inactivation, 62 
Rana pipiens, 38 
Reservoirs (of infection), 12, 16 
Rhipicephalus appendiculatus, 29 
Ringspot (broken), 16 
Ringspot diseases, 32 
Rocky Mountain spotted fever, 82, 88, 89 
Rosette (wheat), 7 
Rous, 3 
Rous sarcoma, 36 
AN INTRODUCTION TO THE STUDY OF VIRUSES 
St. Louts encephalitis, 29 
Sap-sucking insects, 20 
Schultz-Dale technique, 78 
Selective breeding, 86 
Selective transmission, 22 
Shape (of viruses), 60 
Silkworm jaundice, 39 
Size (of viruses), 60, 62 
Slaughter, 85 
Smallpox, 1, 82 
Sodium dodecyl] sulphate, 58 
Sodium hypochlorite, 90 
Southern bean mosaic virus, 69 
Specificity (of vectors), 21 
Squash mosaic, 21 
Starlings, 14 
Streak (maize), 30 
Streptomyces aureofaciens, 89 
Striate material, 51 
Theatrum Florae, 1 
| Thrips, 20 
Ticks, 29 : 
Tobacco mosaic virus, 2, 32, §8, 59, 60, 
67, 69 
properties of, 50 
purification of, 42 
Tobacco necrosis virus, 6, 58, 60, 69 
Tomato bushy stunt virus, 60, 61, 69 
properties of, 52 
Tomato spotted wilt, 20 
Trypsin, 60 
Tulip break, 1 
Tumours, 3, 33, 36, 37, 38 
Turnip yellow mosaic virus, 26, 30, 31, 69 
properties of, 54 
purification of, 43 
Twort, 3 
Typhus, 25, 68, 87, 89 
VACCINATION, 81 
Vaccinia virus, 56, 66 
Vampire bats, 13, 87 
Vectors (miscellaneous), 12 
Virus reservoirs, 88, 92 
WoOvuND tumour virus, 33 
X-RAY diffraction, 61 
YELLOW fever, 21, 23, 83, 87, 88 
