HARDWICKE'S SCIENCE-GOSSIP. 



125 



spikes are mainly instrumental in the production of 

 the new tuber, for how could that new tuber have 

 been healthy and plump, when the old tuber itself was 

 nearly empty ? I am aware, of course, that I cannot 

 argue from a particular to a general case, and so I 

 have stated my theory cautiously. I am also aware 

 that this conclusion is opposed to my remark about 

 the old tuber containing a store of food for the new 

 tuber. The fact is this. I am extremely obliged to 

 G. M. for pointing out the discrepancy in my paper, 

 and thus compelling me to observe more carefully, 

 and I hope that he will observe many plants during 

 this season and help me further. The offending 

 remark was written some time before the remainder 

 of the article. 



Then, another thing. I have succeeded, in two 

 years, in entirely clearing the leaves of a plant of 

 O. mascula of spots, so that the leaves of the plant 

 are perfectly spotless. If the roots supplied the new 

 tuber directly, why should not one year be sufficient 



Figs. 86, 87. — 0. mascula. a, Old tuber ; b, new tuber; 

 c, spike. 



to produce this result ? Look at the drawing atten- 

 tively. The roots are exactly opposite the new 

 tuber, but they join the plant, and the new tuber is 

 connected with the leaves. The spike alone appears 

 to descend to the old tuber. O. mascula appears in 

 a critical case. If the roots are damaged by wet, &c, 

 the plant has to feed on the old tuber, and the spike 

 suffers : if the embryo starts too soon, or remains 

 too deeply buried, the new tuber suffers. If the 

 spike is broken, the old tuber doesn't suffer, but 

 somehow the flower of the following year is 

 affected. 



There were two misprints in my article (vol. xix. 

 p. 52) which have not been noticed. In one place, 

 column was written for collum, and in another, skin 

 for stem. I also made the mistake of calling the 

 embryo the plumule. 



Dr. Erasmus Darwin {Botanic Garden, Canto iv. 

 37) says that the seed of O. mascula only ripens 

 when the tuber is picked off. Then how can this 

 occur in nature, under ordinary circumstances, unless 



some pitiless surgeon of a slug amputates the new 

 tuber ? 



I must apologise for occupying so much space, but 

 I trust the attention focussed on this interesting plant 

 will be excuse enough. 



THE AGE OF THE MALVERN HILLS. 

 By J. Walter Gregory. 



THOSE members of the fraternity of the hammer 

 who have the good fortune to visit the 

 Malvern Hills, will find themselves in a land rendered 

 classic to geologists by the researches of Murchison, 

 Ramsay, Phillips, Horner, Symonds, Brodie, Salter, 

 Holl, not to mention a host of minor names, and in a 

 district into whose varied features as many interesting 

 geological problems and strata are compressed as into 

 any area of England of similar extent. The fossili- 

 ferous Keuper Marl and osseous conglomerate of 

 l'endock and Moorcourt, the splendid sections of the 

 Upper Silurians, West of Worcestershire Beacon, 

 the Mayhill sandstone in its typical locality, the 

 Ludlow Bone bed of Hale end, the noted Permian 



Fig. 8S. — Diagrammatic section of Malvern Hills, a, syenite ; 

 b, gneiss, &c. ; c, Hollybush sandstone ; d, Silurian ; f, Trias. 



breccia of Berrow and Bromesberrow, the Hollybush 

 Sandstone and Black Shales with their lavas of 

 Coalhilland Fowlett's Farm, the Old Red Sandstone 

 of Ledbury, and last but not least the physiography 

 of the Woolhope ellipse, are all in the immediate 

 neighbourhood. 



But to any geologist above the rank of a mere fossil 

 collector, there is one point of surpassing interest on 

 which he is sure to commence, and to which he is 

 tolerably sure to return. However interested he may 

 be in the inversion on the west of the hills, however 

 fascinating he may find the study of the denudation 

 of Woolhope, and the comparison of the wooded 

 undulating Silurian strata of the west with the 

 fertile Keuper plain that stretches away on the east 

 to the Severn, the question of the age of the rocks 

 constituting the chain of hills is sure to retain most 

 of his attention. 



In a series of articles on the Pre-Cambrian Rocks 

 of England and Wales, published in SciENCE- 

 Gossip in 1883, by Mr. W. W. Watts, B. A., F.G.S., 

 the author commenced with a brief notice of the 

 Malvern Hills, which he boldly claimed as Archean. 

 I propose in the present article to see what evidence 

 can be adduced in favour of such a conclusion, to 



