SCIENCE-GOSSIP. 



KSy 



GEOLOGY 



CONDI riKli llV i;i>WAKl> A. MARTIN, F.C.S. 



Kau.na <>i Till-; Ii'.iii'iiAM Fissi'RR.— An account 

 of ihf rLMiiiirkable remains which Mr. Lewis Alibott 

 found durini; his t-xploralion of this famous rock- 

 fissure was pulilisheil liv the Gcolojjical Society in 

 iS94((j.|.(;.S., \ul. L.', pp. lyr ami iSS). SuW- 

 i|ucnlly Mr. .Vlibolt, hy perscvcrinij in his invcsliga- 

 lions, adduil five more vertebrate forms, viz., a large 

 bat, the shoveller-cUicU, and some small p.isserinc 

 birds closely allied to, if not identical with, the red- 

 backed shrike, the chaflinch, and the hedye-sparrow. 

 Subseijuenilv the polecat, otter (?), and swallow were 

 found. The work has since been successfully carrieil 

 on by .Mr. Frank Corner and Mr. A. S. Kennard, ana 

 further valuable finds have been made, which have 

 recently been described by Mr. E. T. Newton. 

 K. U.S. In addition to the main fissure, various 

 collateral fissures have also been explored. Amongst 

 added species are the Roose, peregrine falcon, black- 

 bird (.^), hare {Lepits variahilis), rabbit, Alpine vole, 

 weasvl, wolf (?), cat, and badger. Mr. Newton points 

 out, in the new volume of the"<Juarterly,Iournal," that 

 these contents bear a resemblance to the fauna of an 

 ossiferous fis.sure at Champs Gaillards. This also in- 

 cludes several ntirihcrn species which indicate, in no 

 uncertain way, the extension southward into France 

 of extreme Pleistocene cold. Although evidence of 

 Ihe great Ice Age is wanting in Kent, liere is distinct 

 proot of a great degree of cold, when with the pro- 

 genitors of its present fauna, there also lived the 

 .\rctic aiul Norwegian lemmings, the Arctic fox, and 

 the .Siberian vole. 



Nku- Cakikimkekoi's Lam.mei.i.ibranchs.— 

 Since the pid)lication of Dr. Wheelton Mind's mono- 

 graph (KS95), when he pointed out that only one 

 laniellibranch was known to occur in the L'pper 

 Coal .Measures of C.reat Britain, he has discovered 

 three others, which he lias named Anlhraaviiya 

 lahifii-a, Carhoiii,ola -•htti, and C/enodoii/apciUoiunsh. 

 The first named is found in what is evidently a 

 distinctive zone, which occurs much higher than the 

 zone characterised by A. pliillipsii. The zone of 

 .7. laUifeya is 300 feel below the PenkhuU Sandstone. 



ANciiiNT Watersheds in the South ok Enc- 

 lANl).— From the courses pursued by the rivers of 

 the south coast, it is easy to perceive that these must 

 have been carved out under diflferent conditions as to ■ 

 watershed from those now prevailing. Instead of 

 passing east and west, as they woidd have done, 

 ha<l they commenced to flow while the troughs ami 

 ridges of the Downs and the Wealden area were as 

 now, they run north and south through passages carved 

 out ol the hills. This is so, w hether northward, as 

 the Mole, VVey, and Medway : or southward, as the 

 Cuckmcre. (Juse, Adur and .\nm. The high ground 

 of the dividing w atershed must, at the time of their 

 birth, have been east and west over the Weald, and 

 the easier and (|ulcker course was to carve ncprth. and 

 south, through the minor ranges, and as>ume the 

 physical features which they now present. The fold- 

 ing and denudation which has subsequently taken 

 place here, also shows itself in the Isle of Wight, 



where the course of the rivers show us that upheaval 

 must have been greatest where are now the regions of 

 least elevation. At both ends of the island rivers cut 

 through the chalk downs. These have been enor- 

 mouiily denuded at Freshwater Hay by the work r,f a 

 very much greater river N'ar than is now to be seen. 

 On the east of the island, the present puny river Hows 

 in the culling, so to sjjeak, Ixrtween Brading 

 Down and Kembridge Down. In l)oth cases 

 there are wide alluvial flats on each side of the 

 existing streams, their level being but slightly raised 

 above existing sea-level. It is idle to suppose thai 

 these rivers had their origin in the high Downs which 

 now constitute the backbone of the island, although 

 these may now contribute to the rivers' present 

 existence. .\ thick elephant gravel -bed is exposed on 

 the chalk clifls in F'reshw.ater H.ay, and this is good 

 evidence of the greater extension of the former river ; 

 of ihe denudation which has taken place ; of the 

 extent of land to the south, which the river formerly 

 drained ; of the velocity of its former current ; and of 

 the height of the watershed far aw.ay to the south. 

 Hefore the sea bre.iched the chalk between the 

 Needles and the main land, the FVome, which now 



^^..,f5f?- 



^ftr 



Frkshwatek Gaps, Isle of Wight. 

 emerges at Poole, was the ri\er which here ])assed 

 eastward along one of the great post-Oligocene 

 synclinal folds, and this received as tributaries the 

 northward-tlowing rivers of the Isle of Wight. On 

 the northern side ihis ancient river would have also 

 received the Stour, the .Vvon, and the Itchin : whilst 

 on the south besides the eastern Var, the Medina, 

 and the western Var, it probably also received a 

 tributarv which ran between the Needles and Dorset 

 and along who.se course the sea in later times graduallv 

 encroached, w hen the separation of the island became 

 completed. — E. A. Martin 



Sandstone Tubes. — I .am .sending a specimen of 

 some curious concretionary m.asses occurring in the 

 Upper Grcensand at St. Catherine's Point, Guildf.ird, 

 doubtless familiar to many of your readers. Tliev 

 occur in contorted .sheets and tubes, similar to the 

 sample, frequently over a foot in length. I should be- 

 obliged if you could enlighten me as to their mode of 

 origin. An analysis of the specimen .sent shows it to 

 consist of sand cemented by a mixture of iron oxide 

 and hydrated iron oxide. The interior of the tube was 

 filled with incoherent sand. — Os-.va/J H. Eiaiis. 

 Marlcnv I'lUa, Churchficld Road, Waltoit-on-Thavus. 



[Concretions and tubes of iron sandstone are 

 common in such formations as the Upper Greensand, 

 the Hastings Sands, etc. They originate in the segre- 

 gation of the iron sand around organic nuclei. ' In 

 this instance, the nucleus may have been a sponge, 

 or a cord-like fucoid, which existed sufiiciently long 

 to give the mould to the concretion, afterwards vielding 

 to the usual decomposition. Such impressions and c.ast^ 

 are often the sole evidence obtainable in someformations 

 of the existence of soft, fleshy substances. — E.A. M.] 



