Most of the graveyards (_ying ti_) are very old, and as the centuries pass, the inscriptions on the oldest monuments naturally tend to become illegible or the stones themselves are displaced and broken by the roots of trees or other natural causes. At the periodical sacrifices, however, care is taken to neglect no grave that is recognisable as such. In order to make sure that none of the ancestral spirits will be left uncared for, sacrificial offerings are made to the souls of the ancestors in general as well as to the immediate predecessors of the sacrificers. The usual expression used in Weihaiwei for a ceremonial visit to the family grave is _shang fên_, "to go up to the tombs."[193] A graveyard is very often completely surrounded by cultivated fields. As a general rule these fields are the property of a branch of the family that owns the graveyard, but sometimes the family has emigrated to another part of the country or has had to part with this portion of its arable acres, so that it has passed into the hands of strangers. But the graveyard itself is never forgotten and never alienated. No matter to what distance the family may have moved, it will never lose touch with the spot where lie the bones of its ancestors--the spot to which its members all expect that their bodies will some day be carried. Year by year one or more members of the family will be sent to carry out the traditional sacrificial ceremonies, to "sweep" the tombs and to see that the ploughs of strangers have not encroached upon the sacred boundaries. The most interesting tombs in Weihaiwei, from the visitor's point of view, are those known to the English as Beehive graves.[194] All or nearly all those on which the inscriptions are legible show that they were erected in the Yüan dynasty (1280-1367) or the early Ming dynasty, which came to the throne in 1368. None are of modern date, though in many cases the places in which they are found are still the family burial-grounds of the direct descendants of the people to whose memory they were erected. This handsome form of tombstone has fallen into complete disuse, and the people account for its former use by the explanation that in the old days the country was overrun with wolves and other wild beasts and that it was necessary to erect massive piles of masonry over the graves to protect them from desecration. These tombs somewhat resemble Buddhist stupas or Lamaist _chorten_; most of them have panels artistically carved with figures of animals, human beings and conventional plants and devices of various kinds. Very often the carving on a panel represents the tomb itself in miniature, with mourners or worshippers kneeling round it. The whole structure is made of heavy blocks of stone, the general design consisting of a large dome surmounted by a Buddhistic lotus or a conventional spire and superimposed upon a panelled pedestal.