Nov. 15, 1924 
Relation of Sheep to Climate 
497 
mation regarding the effect of each year 
upon the sheep was obtained (16). The 
years most favorable and unfavorable for 
the Southdown and Hampshire breeds 
were selected. Seasons unfavorable 
for these breeds were unfavorable for 
others in most districts in England. A 
number of meteorological stations were 
selected in south-central England, the 
native home of these breeds and the 
locality in which they are found in 
greatest numbers. Climographs and 
hythergraphs were made from the 
monthly means for the years 1909, 
1910, 1911, 1914, 1915, 1917, 1918, 
1919, and 1921. From the information 
pared with a composite containing the 
limits for April of a good year (fig. 4) it 
falls far below (fig. 8). A composite 
was made for the five months only, be¬ 
cause they fall within narrower limits 
than some other months in the year, 
and come at more critical periods. The 
graphs for several years differ con¬ 
siderably, and do not always fall with¬ 
in the limits of a good sheep year for 
England. One critical month may be 
bad and others good. The graphs for 
1909 at Reading, England, fall within 
the limits of the composite for a good 
year. That year was satisfactory for 
sheep (16), and in particular for the 
Figs. 15 and 16—Growth of lambs at Urbana, Ill., 1907 and 1911 
at hand, the best lambing seasons and 
the most favorable summers, autumns, 
and winters were selected. From these 
were made a composite hythergraph 
and climograph, which represents a 
good sheep year in England. The un¬ 
favorable years can be compared with 
this good year and the contrast noted 
(figs. 6, 7, 8, 9). As the critical months 
of a good year fall within narrow limits, 
a graph was made for February, March, 
April, May, and June of the good years 
(fig. 4). For example, too cold an 
April of any given year, when com¬ 
pared with the composite hythergraph 
and climograph, might fall within the 
limits of a good year; but when com- 
lambing season (fig. 5). The following 
selected case serves to illustrate bad 
years due to unfavorable critical 
months and to poor food .and water sup¬ 
ply. The summer of 1911 at Hastings 
was hot, and July was very dry; the 
humidity was high in July and August; 
and October, November, and Decem¬ 
ber were very wet (fig. 6). This was 
noteworthy because of the small num¬ 
ber of twin lambs, the failure of food 
crops, and the low price of mutton. 
From Figure 7 it appears that March, 
1914, at Reading was too wet. Early 
lambs were weak and mortality was 
heavy. December of the same year 
was exceedingly wet, and ewes lost 
