CLASS MAMMALIA. 59 Family MURIDAE. Genus Mus, Linn. Mus minutus, Pallas. Harvest Mouse. This very beautiful and active little creature occurs in all parts of Essex. In the winter time, it is found in corn-stacks, especially those placed in the fields, and most frequently, I think, in oat-ricks. I never discovered more than a dozen in one rick, although others have informed me that they have been found more abundantly in such situations. As a pet, the Harvest Mouse is very interesting, and rarely quiet, day or night. They are very peaceable all through the winter, and any number may be kept together ; but, in the spring fighting goes on until all, or nearly all, the males are destroyed and eaten, for they are dreadful cannibals. On the whole, I can strongly recommend them as pets. They are sweet, not at all mousy in odour, and very amusing in their ways. The longest time I have had them in confinement is over two years, but I never could make them so tame as my pets of the next species (Mus sylvaticus). I have taken every precaution possible, but have never been able to get them to rear their young in confinement. All might proceed well for a few days, and then their cannibal tastes would be indulged in, and the entire brood of young would be destroyed and eaten. Indoors, Harvest Mice do not become torpid ; nor do they when living in corn-ricks. I have never found any young in corn-ricks, although they are said to breed there. I consider their breeding-season is entirely confined to the summer months. This habit perhaps helps to prevent them becoming the pests to the farmer and gardener that some of the other mice undoubtedly are. Their numbers also are so small, they never can do much damage ; and, as their