423 
week in advance, will be filled with sterile nutrient agar, or witl 
potato dextrose agar for the study of bacteria and molds. 
SPECIMENS AND MOUNTS FOR EXHIBIT 
Illustrating the principles of genetics: 
Pea seeds illustrating a dihybrid ratio (wrinkled, smooth, yel- 
low, green). 35. In vials. 36. Riker mount. 
37. Jimson weed (Datura)—mount to show F, segregation of 
spiny and smooth pods. 
Corn showing monohybrid and dihybrid ratios: 
38. Ears of parents and F,—seed of F, in vial—un- 
mounted. 
39. Same mounted in glass covered display case 
40, F, ears in glass tubes—for counting kernels. 
41. Sorghum—Hybrid vigor—Riker mount of parents and F,. 
42. Sorghum—Inheritance of seed color—Riker mount. 
43. Oat ian inheritance of hull color—Riker mount. 
44, Snapdragon—Inheritance of flower color—Riker mount. 
Economic plants: 45. Bundles of cereal grains (barle 
rye, sorghum, wheat). 
Fungi and plant diseases: 46. Bracket fungi ted. 
Leaves showing leaf s 
y, oats, rice, 
— 
y0t diseases ate mildews, and others). 
47, Unmounted. 48. Mounts covered with cellophane 
49, Riker mount—specimens of six diseases. 
Mosses and Ferns: Mounts covered with cellophane. 
50. Life history of a moss plant—Polytrichum commune. 
A bd 
ANGIOS pe Pres 
51. Riker mount showing leaf modifications. 
52. Fruits of trees, flowering plants, weeds, lotus pods—loose 
53. Riker mount to show methods of seed dispersal. 
LIBRARY 
The rapidly growing library of the Garden comprises at present 
about 20,000 volumes and about 17,000 pamphlets. This is not 
a circulating library, but is open free for consultation to all per- 
sons daily (except Sundays and holidays) from 9 a.m. until 5 p.m. 
(Saturdays, 9 to 12). More than 1,000 periodicals and serial 
