THE RELATION OF DIET TO DISEASE 459 
and milk products. Non-pathogenic saprophytes carried 
in milk produce (1) a poison closely allied to tyrotoxicon, 
(2) a toxalbumin which in itself causes serious disturb- 
ances. Botulism, also probably of this group, is a disease 
initiated by a toxin elaborated by Bad. botulinus acting 
on a protein. There is, however, some evidence that Bad. 
hotulinus can also establish a real infection. 
The toxemias from food infected with bacteria may not 
occur until the food is ingested or the bacteria implanted. 
This result occurs in infections with Bad. bovis morhif- 
icans, Gartner's bacillus, etc., or after the feeding of 
meat from animals infected with Bad. paratypliosus 
and enteritidis. 
The plant poisons are more frequently due to inherent 
injurious substances, although even among them, bac- 
terial and fungus diseases play an important role. 
Among the 16,673 plants indigenous to North America, 
almost 500 are more or less poisonous and about 30 
are of great economic importance. The toxic factor may 
be confined to the leaf, seed or root, but more often it is 
associated with all parts of the plant. Through the efforts 
of the Department of Agriculture a more or less complete 
list of the plants implicated in the poisoning of stock has 
been compiled. This list includes the following : Amanita 
muscaria; A. phalloides ; Veratrum viride; Phytolacca 
decandra; Agrostemma githago; Delphinium, 25 varie- 
ties; Astragalus mollissimus; Aragallus lamhertii; 
Crotalaria sagittalis; Euphorbia lathyris; E. marginata; 
Rhus radicans; R. diversiloba; R. vernix; Aesculus pavia; 
A. hippocastanum; A. glabra; A. Calif ornica; Cicuta 
maculata; C. vagans; Conium maculatum ; Kalmia lati- 
folia; K. augustifolia; Leucothoe catesbaei; Rhododen- 
dron maximum; Pieris mariana; Datura stramonium; 
Solanum nigrum; S. dulcamara; Uelenium autumnale; 
Asclepias pumila; A. verticullata; A. galoides; A. mexi- 
cana; A. eriocarpa; A. speciosa; A. fremonti; Eupa- 
torium agertoides; E. urticar folium; Isocoma wrightii; 
