THE HARVEST MOUSE 571 
even feathers and scraps of wool. . . . I do not know whether 
it is universally the case that the buck assists the doe Harvest 
Mouse in the task of nest-making. But it does sometimes, 
and it is a pretty sight to see the two working together. 
Although the shyest of rodents, they do not seem to notice 
the observer if he remains perfectly still and carefully refrains 
from making any noise.” 
The nest of the Harvest Mouse is built for the special 
purpose of providing a safe and convenient nursery for the 
young. From White’s day onwards much has been written 
about the young completely filling the nest, and consequent 
inability of the dam to sleep in it with her babies. White 
suggested that the dam had to open a different place in the 
periphery of the nest in order to suckle each of the young ; 
while Johnston thought that they might even be suckled 
outside the nest. English says, however, that the babies get 
proportionately as much space as would young House Mice. 
Mr Rope (of. cz¢., 1884, 58) remarks on the superior archi- 
tectural skill of this mouse, which can arrange its bedding in 
a square box in a round, compact nest resembling the spring 
and summer nurseries. 
The Harvest Mouse appears to be, at least in summer, not 
less prolific than other murines, giving birth to several litters 
in each season.’ The number ina litter appears to vary between 
five and nine, and gestation” is believed to last twenty-one days. 
The young are born naked and blind, and they attain the adult 
stature in six weeks.* Dr H. Laver has never met with the young 
in cornricks, ‘although they are said to breed there” ; he con- 
siders the, breeding season to be confined to the summer months. 
1 The following are the principal observations on the number of young in a litter :— 
Nine recorded by Pallas; in a nest in Brittany (E. D. Cumming) ; in Lancashire, 
M. Saul, Zoologist, 1843, 349; and by Gloger in Bell, ed. ii, 290. Eight by White 
(Letter xii.) ; Bingley, 267 (September 1804) ; in nest, Sussex, L. E. Adams (2m Jz). 
Seven on three occasions, D. English (of. c7z¢., 83). Six to eight several times in 
Suffolk, Moor, Zoologist, 1884, 190. Six or seven naked and blind in nest, Macgillivray. 
Six in a nest lined with roots and fibres, not so compact as White’s nest, but round 
as in his description, Jenyns, Ods. Mat. Hist, 73, 29th July 1826, Five, Gloger 
in Bell, ed. ii., 290. G. W. Murdoch found two young but full-grown mice in a nest 
and three empty nests, in Shropshire in 1872 (Zoo/ogzst, 1895, 447). 
2 j. E. Harting, Zoologist, 1895, 421. 
* J. H. Blasius, Saugethiere Deutschlands, 329. 
