HARDWICKE'S SCIENCE-GOSSIP. 



187 



in the discovery of more satisfactory specimens, 

 which have been examined by Messrs. Carrutliers, 

 Etheridge, and E. T. Newton. Among them are 

 spherical bodies resembling the Pachytheca of Sir 

 J. D. Hooker, from the bone-bed of the Ludlow 

 series, supposed to be Lycopodiaceous spore-cases ; 

 also numerous minute bodies stated by Mr. Car- 

 ruthers to be united in threes, and to agree with the 

 forms of the microspores of Lycopodiacex, both 

 recent and fossil ; and some fragments, which may 

 belong to these plants, and others, probably belong- 

 ing to plants described by Dr. Dawson from the 

 Devonian of Canada under the name of Psilophyton. 

 The above testify to the existence of a very rich 

 land-flora at the time. Mixed up with these, how- 

 ever, are numerous carbonaceous fragments of a 

 plant described also by Dr. Dawson from the 

 Devonian of Canada, which he referred to the 

 Coniferje, but which is, according to Mr. Carruthers, 

 an anomalous form of Alga. The former called it 

 Prototaxites ; the latter renamed it Nematophycus. 

 Numerous microscopical sections, showing the 

 beautiful structure of this interesting plant from the 

 specimens found at Pen-y-glog, have been examined 

 by Mr. Etheridge and Mr. Newton, and their con- 

 clusions agree with those of Mr. Carruthers. The 

 evidence seems to show that at this mid-Silurian 

 period the immediate area where the plants are now 

 discovered must have been under water, and that the 

 mixture of marine and dry-land plants took place in 

 consequence of floods on rapid marine denudation. 

 The author indicated that the land-areas must have 

 been to the south and west, chiefly islands, sur- 

 rounded by a moderately deep sea, in which Grapto- 

 lites occurred in abundance. The position of these 

 beds is about 2000 feet below the true Wenlock series, 

 and about the horizon of the Upper Llandovery rocks. 



"The Diamond-fields of South Africa." — 

 A paper on this subject has been read before the 

 Geological Society by Mr. J. Dunn. The passes or 

 necks of decomposed gabbro, cS:c., at the Kimberley, 

 Bulfontein, and other diamond-mines have now been 

 excavated to a considerable depth, and have allowed 

 excellent sections of the sedimentary beds through 

 which they have broken to be examined. These are 

 generally but little disturbed, and may be traced over 

 an area of many square miles. Immediately beneath 

 the surface are, generally, yellowish shales, with 

 remains of small Saurians ; and beneath these a mass, 

 certainly more than a hundred feet thick, of black 

 carbonaceous shales, with occasional thin bands of 

 coal. It is found that the diamonds are more 

 abundant and of better quality when the level of the 

 black shales is reached. It seems, therefore, not 

 improbable that the carbon requisite for the forma- 

 tion of diamonds was obtained from these shales. 

 Some other points of minor interest were also noted 

 in this paper. 



'• Fertility."— By this title Dr. J. B. Lawes 

 has published a brochure (London : D. Bogue) of 

 seventy pages, in which is concentrated a really 

 voluminous mass of experimental information relating 

 to agricultural chemistry. Dr. Lawes' chief en- 

 deavour is to show the value of latent nitrogen in 

 soils. We very cordially recommend this little work 

 to every one who is in any way interested in agri- 

 culture. 



Prehistoric Hackney.— London seems to be 

 the last place to look for prehistoric interest, but 

 both geologist and archaeologist are aware how full 

 its neighbourhood is of this kind of association. 

 Mr. J. E. Greenhill has recently read a paper with 

 the above title before the Hackney Microscopical 

 Society, in which all that is geologically interesting 

 about the locality is very ably and clearly set forth. 



NOTES AND QUERIES. 



Birds in North America. — I would like much 

 to know what bird your correspondent, W. T. Greene, 

 can mean by "the Virginian Nightingale from the 

 Southern States of America," as mentioned in 

 Science-Gossip for April, 1881. I have spent much 

 time in our Southern States and thought I was 

 familiar with all the song birds and most of their 

 "local" names. The mocking bird {Turdus poly- 

 glottus) is frequently a delighful night-singer both 

 in his native freedom and in captivity — but Dr. 

 Greene can certainly hardly mean this, for he speaks 

 of its scarlet colour, &c., and also says, " but it is 

 scarcely a desirable subject to acclimatise, as our 

 gardeners have plenty of native pests to contend 

 against without adding another to their number." 

 The mocking bird could never be a pest — except in 

 taking a few cherries, &c. — it delights in spiders, cater- 

 pillars, grubs, and is a most delightful bird whether 

 in captivity or free. I have often wondered that it 

 has not been acclimatised in England. It would 

 certainly thrive with the open-air treatment that 

 Dr. Greene speaks of, it would live anywhere the 

 thrush would with you, and would be no more of a 

 pest than thrushes. I am almost tempted to say that 

 I will furnish a young pair delivered in Liverpool 

 during September next if Dr. Greene will undertake 

 the experiment — with the understanding that the 

 young birds as soon as able to fly shall be set free 

 and attended to for a while with a view to their 

 thorough acclimatisation, if possible. I know of no 

 bird worthy the name night-singer that at all 

 corresponds with Dr. Greene's description. There is 

 too much ignorance of natural things in these two 

 countries of ours, and we Americans sometimes see 

 in your papers some things ridiculous to us. As a 

 case in point allow me to quote from the London 

 "Daily Telegraph" of Nov. 27th, 1877, when I was 

 in England and cut the article out of a copy of that 

 paper. The article was on acclim.atisation and is 

 a long one. The part which seemed so ridiculous to 

 us was the following sentence : "In like manner the 

 citizens of New York thought it would be advan- 

 tageous to introduce the English sparrow mto their 

 new Central Park, with a view to killing the kabydias 

 and other insects of the caterpillar tribe with which 

 the green trees of the United States swarm and are 

 vocal during the hot nights of summer." The funny 



