NOTES AND QUERIES. 



161 



ferruginous, argillaceous, calcareous, or siliceous. On the third point we request 

 information from the secretaries and members of such institutions. 



W. S. ( Bristol), — -'Sir, — Can you give me any information in the next number of 

 the Geologist as to the fossil remains called Palates — are they the teeth, or 

 are they any other parts of mammals, fishes, or reptiles ? I have consulted -various 

 books, but in none of them can I find any reference to them. I have collected 

 up to the present time, in this neighbourriood, about twenty different kinds, and 

 should much like to know in what work I could find out their designations." — 

 The " Palates " alluded to by W. S. are the dental plates — crushing teeth, in fact — 

 arming the jaws of certain species of sharks and rays. The fish of the cretaceous 

 sea, whose palates are so well known in the chalk, have their nearest living re- 

 presentative in the Cestracion of Port Jackson (Australia). The palates from 

 Bracklesham Bay have their representatives in the Eagle- rays of our present 

 seas. We shall shortly print, in our gems of private collections, a more ample 

 notice of these remains. Agassiz's great work, the " Poissons Fossiles," is the 

 great authority for fish remains ; but its price necessarily renders it a scarce work. 

 W. S. will find notices of these fish palates in Mantell's " Wonders," and Lyell's 

 ** Manual of Geology." 



H. W. (Bury St. Edmunds). — " I should be much obliged if you or any of your 

 correspondents could inform me of the probable cause of the occurrence of thick 

 veins of sand that are found penetrating, or rather filling up deep cylindrical 

 holes in, the chalk, often to the depth of thirty feet or more ; they are called by 

 the quarrymen ' sand golfs, or gulfs.' We are in this neighbourhood upon the 

 upper chalk formation, with regular layers of flints (horizontal), and the chalk of 

 a moderate hardness." — When the chalk and the Tertiary deposits lay level pre- 

 vious to the upheaval of the Wealden dome, the drainage water of the Tertiaries 

 could only pass off by filtering down perpendicularly through the chalk. The 

 water thus filtering downwards is considered to have been impregnated with 

 acidulous gas, and by this means to have acted with energy on calciferous 

 rocks in dissolving out these pipe-like cavities, into which, as by this action 

 they were constantly being deepened, the superincumbent tertiary sands 

 and clay gradually sank. But after the lifting up of the Wealden area the 

 surface waters went off by the slopes of the higher ground into the lateral 

 valleys. In Dorsetshire and Wiltshire these beds are still horizontal, and in the 

 large districts of Bagshot Sand, yet remaining in situ, many " swallow-holes " 

 or cavities occur, in which streams or water- courses suddenly disappear. Such 

 is the commonly received notion of the sand-gulfs H. W. alludes to, which are 

 more generally known as sand-pipes. Mr. Prestwich follows Sir Charles Lyell 

 and others in considering these pipes to be the effects of water, charged with car- 

 bonic acid gas ; and there are some excellent papers on the subject by that gentle- 

 man in the Tenth Volume of the " Geological Journal," p. 222 and p. 241, and in 

 the Eleventh Volume, p. 64. The late Mr. Trimmer considered these sand-pipes as 

 due to the waves of the sea, in producing a vorticose action ©f pebbles and sand at 

 the termination of long furrows in the surface of the chalk, by which these long 

 cylindrical or conical cavities were " wormed " out, as it were, by a kind of natural 

 auger or drilling machine. Mr. Trimmer's papers will be found in Vol. X. 

 of the " Geological Journal," p. 231, and p. 274. 



R. G. E. justly complains that having written in reply to an advertisement 

 in our second number, offering an exchange of fossils, he has had his letter re- 

 turned through the Dead Letter Office. R. G. E. also offers to exchange crag 

 fossils for any specimens from beds below the greensand ; but as the initials are 

 the only signature to the note we have received, and London the only address, we 

 cannot do more than acknowledge our correspondent's letter, as our readers would 

 be in a similar dilemma to himself in any attempt at correspondence or exchange. 

 We have learned from the late proprietor the name of the advertiser, and can but 

 think the return of our correspondent's letter a mere accident. 



A Young Inquirer. — "Sir, — Can you give me an explanation of the extraordinary 

 abundance of oxide of iron in the Red Crag of Suffolk, as shown by the deep colour 

 of the fossils, and their matrix ? I have been rather puzzled by a curious fossil from 



