Welsh Journals

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zone that man has dammed many pure streams and constructed impressive reservoirs. Finely planned and beautifully kept the reservoirs supply cities like Cardiff, Liverpool and Birmingham with regular supplies of unpoluted water, add much additional charm to the Welsh landscape and every year attract many tourists. THE STATUS OF LUNULARIA CRUCIATA (L). DUM., IN ENGLAND AND WALES. GORDON T. GOODMAN. Department of Botany, University College of Swansea. The liverwort Lunularia cruciata (L.) Dum., is so widely distri- buted in the British Isles that it is a familiar sight along the sides of streams, ditches, old walls, or hedgebanks, and in many other, usually man-made, habitats. Its ubiquity is curious when one considers that the plant is almost entirely barren its reproduction by sex-organs is virtually unknown in Britain. The species has also been consistently recorded as sterile in northern Europe, but apparently, on very rare occasions, it may produce fruiting stages in southern Europe and the United States of America. Lunularia is spread almost wholly by minute, green disc-like gemmae" which become detached from the parent and are carried away in trickles of rainwater, etc., ultimately growing into new adults. These non-sexual, gemmae can be seen on the upper surface of the plant, grouped together inside small crescent shaped pouches (Fig. i) whose characteristic shape serves to distinguish this species from all other British hepatics. On the rare occasions when sexual reproduction does occur, it is found that the sexes are separate, there being female plants which may be fertilized by sperms from male plants, in which case, a small, upright, rod-like structure bearing spores (carpocephalum) is produced on the female (Fig. i). So uncommon is the occurrence of sexual and spore-bearing stages that the only known records in Britain are confined to the last hundred years and the following list appears to be all the available cases recorded by naturalists Female Plants :-Staffordshire, V.C. 39 Glamorgan, V.C. 41 Anglesey, V.C. 52 Mid-Lancashire, V.C. 60 N.E. Yorkshire, V.C., 62 (from six different localities). Male Plants W. Cornwall, V.C. i (one locality only). Sporogonial (Spore-bearing) Plants :-W. Cornwall, V.C., i S. Devon, V.C., 3 S. Somerset, V.C., 5 E. and W. Sussex, V.C's 13 and 14 Surrey, V.C. 17 and Middlesex, V.C. 21 (from nine different localities).