898 



INDEX 



Pastinaca sativa 228-230, 788, 796, f. 

 229 

 Distribution 719, m. 230 

 Seed f. 688 

 Pasture Thistle 651 



Weeds 838, 845 

 Patience Dock 763 

 Patrick, G. E., 826, 837 

 Pavon, J. 753 

 Pawpaw 687 

 Pea 180 



Partridge, Distribution 718 

 Sweet 180 

 Wild 790 

 Peach 175, 632 

 Peach-leaved Dock 78-79 

 Pear 175, 632 

 Pearl Grass 664. 665 

 Pease, A. 845 

 Peavine Clover, Seed 812 

 Pedicel 868 

 Peduncle 864 

 Pegomyia betae 676 

 Pelargonium f. 602 

 Pellitorv 72-74, 788, f. 12, 73 

 Distribution 738, m. 736 

 Wall f. 597 

 Pennisetum typhoideum, Seed 813 

 Pennsylvania seed investigations 831 

 Smartweed 90-91, 430-431, 645, 657, 



658, 659, 660 

 Weed legislation 794 

 Weeds 750, 759, 765, 768, 839 

 Pennvcress 143-144, 788, 793 



Distribution 692. 699, m. V,', 

 Seed Ml, 814, 815, f. l,',l 

 Field, Seed 814 

 Pennvroval 268 



Pepper. Water 92-93, 594, 775, f. 93 

 Distribution 734 

 Seed 430, f. 1,29 

 Mild 95-97, 594, 788, f. 95 

 Distribution m. 96 

 Seed 430, f. $29 

 Peppergrass, Large 144-145, f. V,'< 

 Distribution 717, 728, in. l',5 

 Seed 441-442, 539-540 

 Small 146-147, f. 11,6, 692 



Distribution 691, 717, 734, m. 11,7 

 Seed 441, 540, f. 1,1,2, 51,1, 638, 688 

 Southern 723 

 sp. 660, 785 

 Diseases 678 

 Seed 674, 815, f. 676 

 Virginia syn. Large Peppergrass 

 Wii<l sun. Larpe Peppergrass 

 Peppermint 268, 709, f. 270 



Distribution 720 

 Percival, John 677, 825, 843 

 Perennial Rag-weed 331-332. 651, 689 

 Rve Grass 420-421. 789, 811, 813 

 Sow Thistle 394-396, 499, 663, 753, 

 793, 808, 814, 819, 826, 842 

 Perennials 648-649, 650, 691, 695, 786, 



868 

 Perfect flowers 605, f. 60', 

 Perianth 609, S68 

 Pericarp 516, 868, f. 516 

 Peridermium pini 678 

 Perigynium 868 

 Perigynous flowers f. 610 

 Perisperm 868 

 Peronospora effusa 678 



parasitica 677. 678 

 Perrin, C. M. 750 

 Persiearia svn. Lady's Thumb 

 Persimmon 687 

 Pertinacity of weeds 714 

 Peru, Weeds of 753 

 Petal 604, 868 

 Peter, A. M. 837 

 Petersen, N. F. 845 

 Peterson, C. E. 762 



Peterson, Maude G. 854 



Petiole 591, 868, f. 591 



Petunia grandiflora, Distribution 727 



rhacelia sericea, Distribution 695 



tanacetifolia, Distribution 738 

 Pheasant as seed destroyer 629 

 Phenology of weeds 785-790 

 Philadelphia Lily 689 

 Phleum pratense f. 505 

 Distribution 715 

 Seed 414-415, 517, f. 1,11,. 505 

 Phloem 868, f. 598 

 Phlox drummondii, Seed 829 

 Phorbia brassicae 677 

 Photosynthesis 516, 599-600, 868 

 Phragmites communis, Distribution 



733, 736 

 Phvllotreta nemorum 676 

 Physalis heterophylla 279, f. 280 

 lanceolata 279-2 80, f. S80 



Distribution in. 280 

 pubescens, Seed 569, f. 568 

 sp. 651, f. 623 

 subglabrata 279. 789 

 virginiana 279, 281 

 Distribution in. 281 

 Phytolacca decandra 776 

 Distribution 705, 763 

 Phytolaccaceae 3. 776 

 Bibliography 586 

 Distribution 763 

 Pickerel Weed, Distribution 712 

 Picris echiodes. Seed 497, f. 1,98 

 Pieper, H. 82 8 

 Pie-plant 74 

 Pierce, R. E. 749 

 Pieters, A. J. 583, 835, 859 

 Pigeon Grass 17-20, f. 18 



Chemical composition 19 

 Distribution 714, 732, m. 19 

 in cornfields 17 



Seed 22, 413, 640, 814, f. U3, 676 

 Pigweed 



(Amaranthus) 113-115, 645, f. Ill,, 595 

 Chemical composition 115 

 Distribution 716, 723, 734, 737, 



m. 115 

 Seed 434, f. 1,35. 636. 676 

 (Chenopodium) 67, 107-109, 664, f. 

 108. 217 

 Chemical composition 109 

 Distribution m. 109 

 Family 113-119 



Seed 434-435 (See Amaranth) 

 Green (A. retroflexus) syn. Pigweed 

 Prostrate 117-118. 788, f. 117 

 Distribution 716, m. 117 

 Seed 4 34, f. 1,31, 

 Rough syn. Tumbling Pigweed 

 Russian, 'Seed 814 

 sp. 657, 687, 723, 786, 834 

 Spreading sun. Prostrate Pigweed 

 Tumbling 115-116. 790, f. 116 

 Distribution 716, m. 116 

 Peed 434, f. 1,35, 638 

 Winged 99-101, 788, f. 100, 101 

 Distribution 693, 716, in. 100 

 Seed 451, 740, 746, f. 1,31, 730 

 Pilose Eragrostis siin. Spear Grass 

 Pimpernel, Distribution 719, 740 

 Pine 3, 6 



Cluster-cup 67 8 



Lodge-pole. Distribution 694, 695 

 White 6 

 Pink f. 606 

 Dalea 454 

 Family 120-134. 435-438, 533-536 



Distribution 724 

 Garden 120 

 Parosela 192-193 

 Smartweed 86-87, 4 30, 742 

 Pineapple Weed, Distribution 725. 729 

 Pinus murrayana, Distribution 694 



