272 THE PLANT WORLD 



materials used as antidotes, and instruments employed in administering 

 antidotes to live stock which have eaten poisonous plants. Instruments 

 used in autopsies and in the laboratory are also included. 



Active principles of plant poisons. — On the other side of the case, 

 dried material of a number of species and small quantities of active prin- 

 ciples isolated from American poisonous plants are shown. 



Potted plants. — Potted specimens of some of the most important 

 poisonous plants are exhibited. 



GRASS AND FORAGE PLANT INVESTIGATIONS. 



The exhibit of the Office of Grass and Forage Plant Investigations is 

 composed chiefly of the following groups of material : 



Models of haying machinery. — Models of hay balers, stackers, rakes, 

 and other types of machinery used in haying operations ; photographs of 

 machinery ; samples of smaller articles, such as baling ties and soft- 

 ground horseshoes. 



Baled hay. — Samples of ordinary hay of a few standard varieties ; 

 double compressed bales used for export ; a wireless bale ; and several 

 bales illustrating the miscellaneous hays of the country. 



Mower parts. — The pitman attachments of several makes of mowing 

 machines, showing the connection with the crank wheel and sickle — one 

 of the most important parts of a mower. 



Model of sand dune. — A miniature sand dune, illustrating methods 

 used to control drifting sand, such as plantations of beach grass, cover- 

 ing with sand hedges, and the foundation of a barrier dune. 



Seeds of forage plants. — Seeds of about forty of the leading forage 

 crops are displayed in half-gallon glass vials, while many distinct varieties of 

 cowpeas, soy beans, sorghums, and millets are shown in smaller vials. 



Silo construction. — The central pavilion in this exhibit is a cylinder 

 13 feet in diameter and 12 feet high. The interior is reached through 

 four doorways, in the sides or jambs of which are built cross sections 

 showing actual silo construction. Four types of silos are thus illustrated ; 

 namely, a stave silo, two kinds of round wood silo (one merely sheathed, 

 while the other is lathed and covered with cement plaster), and a round 

 brick silo. 



Dried grasses and forage plants. — Upon the walls of the central pavilion 

 or silo are placed sheaves and dried specimens of native and cultivated 

 grasses, alfalfa, and other forage plants from all parts of the United States. 



POMOLOGICAL INVESTIGATIONS. 



1. Commercial apples of the Mississippi Valley. — A collection of models 

 of the leading commercial varieties of apples grown in the Mississippi 

 Valley and Upper Lake regions occupies two case fronts. This collection 

 consists exclusively of such varieties as have demonstrated their adapta- 

 bility to commercial culture in various sections of the region extending 

 from the Great Lakes to the Gulf. It comprises varieties ripening through- 

 out the season from early June in Texas, Louisiana, and Mississippi, 

 until late October in the more northern States. 



2. New or little-known apples of the Mississippi Valley. — A collection 

 of new or little-known varieties of apples that are considered worthy of 



