============================================+========================= _Animals that have since become extinct._ |The same as in the | preceding period The Irish deer, the big-nosed rhinoceros, | with the exception the mammoth, the straight-tusked elephant,| of the big-nosed the cave-bear, and the sabre-toothed | rhinoceros and the _felis_ were survivals of an earlier | sabre-toothed _felis_, period and were accustomed to a warm | which were extinct. climate. | All of the animals | named became extinct at The small-nosed rhinoceros came from the | the close of this south and the woolly rhinoceros came | period. down from the north during this period. | | At the close of this period the big-nosed | rhinoceros and the sabre-toothed _felis_ | becameextinct. | --------------------------------------------+------------------------- _Animals that have since migrated._ |General invasion of | Arctic animals. The musk-sheep and the marmot came down | from the north during this period, stayed |At the close of the through the next period and then migrated | period they migrated to the Arctic regions. | to the north. --------------------------------------------+------------------------- _Living species._ |The same except that | those animals that In addition to those that migrated there | could not stand were the lion, panther or leopard, lynx, | the intense cold, wild-cat, spotted hyena, hippopotamus, | migrated south brown bear, grizzly bear, wolf, fox, stag,| each winter. roe, urus (the original form of the wild | cattle), aurochs or European bison, horse,|Arctic fauna wild boar, beaver, and water rat. Many of | characteristic of this these animals migrated south in the | period. winter and returned each spring. | --------------------------------------------+------------------------- _Field Trips._ In localities where the natural materials needed for the child’s work are near at hand it will be best to gather them immediately before they are to be used. In regions less favorably situated it will undoubtedly be best to plan the work so as to make a few trips serve the purpose. Perhaps the trips most needed to make the lessons of this book yield their full value are the following: 1. To a stream of water to notice: (_a_) The wearing and building power of the stream. (_b_) The location and the strength of the current. (_c_) The best places for fords and for bridges. (_d_) The tributary streams and springs.