26 BULLETIN 1082, U. S. DEPARTMENT OF AGRICULTURE. 
The crates should be constructed so that a definite number of 
sacks will fit snugly. (PL XIV, Fig. 2.) 
IMPORTANCE OF CLOSELY SIZING MERCHANTABLE STOCK. 
The value of bulbous stock is dependent in a very large measure 
upon its uniformity of performance under either forcing or bedding 
use. One of the most important factors governing this uniformity 
is the size of bulbs. It is consequently important that the merchant- 
able stocks be closely sized, for the effectiveness of the planting de- 
pends upon having the plants alike, the flowers uniform, and the time 
of flowering the same. 
SIZES. 
Tulip bulbs are measured in a rather peculiar way, from the Amer- 
ican viewpoint. We speak, for instance, of a 12-centimeter bulb, 
meaning presumably that the bulb measures 12 centimeters in cir- 
cumference, but it seldom does, owing to its angularity. Although 
we speak of sizes in circumferences, it is after all diameter that is 
measured, because the size of a tulip bulb is the periphery of a circle 
whose diameter is equal to the greatest diameter of the bulb. The 
bulb caliper (PI. X, Figs. 1 and 2) is a round hole. Bulbs which pass 
through an 11-centimeter orifice or screen and are caught by a 10- 
centimeter screen are called 10 to 11 centimeter bulbs, although the 
individuals may differ widely in actual quantity of material. This 
is probably as fair a method as any for measuring such irregular 
objects. 
The sizers are usually so built that sizes varying 1 centimeter in 
circumference may be sieved out. It is then possible to recognize as 
many sizes as there are unit centimeters between the smallest and 
largest size of tulip bulb, or about 12 sizes. In practice, however, 
the commercial tulip is sorted into two or three sizes, usually referred 
to as first, second, and third grades or sizes, though the mechanical 
sizing of tulips has no element of grading in it. Grading is done by 
culling by hand all imperfect bulbs. Having picked out his commer- 
cial sizes, which are mostly above 10 centimeters, the grower resorts 
to a sizing of the remaining bulbs for his planting stock. It will be 
seen that the bulk of the Bureau of Plant Industry planting stock 
runs 8, 7, 5, and under 5 centimeters. The 5-centimeter size really 
extends from 5 to just below 7 centimeters. 
It should be noted that a sizer in the form of a grating (PI. XV, Fig. 
2) will not give the same results as one having round openings for the 
bulbs to pass through (PL X, Fig. 3) . In the one case the greatest 
diameter governs and in the other, the shortest. 
WEIGHTS AND MEASURES. 
With objects of such variable dimensions as tulip bulbs it is mani- 
festly as impossible to arrive at absolute accuracy in connection with 
