HARDWICKE'S SCIENCE-GOSSIP. 



279 



GEOLOGY. 



Sedimentary Basalt (Doleryte).— In the co. 

 Antrim, between Portrush and the Giant's Cause- 

 way, there is a series of thin-bedded dolerytes under 

 the great massive sheets. These beds have all the 

 appearance as if they were originally sedimentary 

 rocks. I however do not believe that they are now 

 in their normal condition, but that originally they 

 were basic tuffs or tuffose rocks ; that is, they were 

 either ejected as tuff, and afterwards sorted and 

 arranged by water, or they were made up of the 

 detritus of disintegrated doleryte, and were arranged 

 by water in their present bedded condition ; while 

 subsequently they were invaded and altered by the 

 same metamorphic action as that which metamor- 

 phosed the Lias rocks at Portrush. It seems im- 

 possible these rocks can be normal dolerytes, as no 

 outburst of igneous rocks, no matter how fluid, 

 could form such widespread, thin, and even sheets ; 

 neither is it likely that their present bedded appear- 

 ance is due to a system of horizontal jointing. 

 Furthermore, we know that rcetamorphism has 

 changed felsitic tuffs and tuffose rocks into a rock 

 undistinguishable from felstone; therefore it is 

 probable that the same action is capable of changing 

 basic tuffs into rocks undistinguishable from do- 

 leryte. If this is the case, we have a doleryte 

 (not normal however) that originally was a sedi- 

 mentary rock. — G. H. Kinahan. 



1 Fossils near Watford (p. 263).— The chalk-pit 

 in Berry Wood, Aldenham, about which " W. H. G." 

 inquires, is still accessible, but I fear the geologist 

 who visited it in expectation of finding it " abounding 

 in well-preserved fossils of various kinds" would be 

 disappointed. The fossils referred to are preserved 

 in the cavities of flints, and are mostly microscopic ; 

 and their abundance is merely due to these hollow 

 flints being more frequently met with here than in 

 other places where the chalk is exposed in the 

 neighbourhood of Watford. The heaps of chalk 

 from the new tunnel will be found better worth 

 searching for fossils. — /. //., Hon. Sec. Watford 

 History Nut. Society. 



NOTES AND QUERIES. 



White Woodcocks.— Was the bird mentioned 

 by Mr. Wolstenholme a pure white or a yellowish 

 white (pale-fawn colour) ? — as yellowish white wood- 

 cock and snipe are not so very rare in Ireland, a 

 good collection being in the museum of the Royal 

 Dublin Society. 



The Sixth Century Irish Churches and The 

 Ark of the Covenant. — To me it always seemed 

 likely that the early Irish churches were copied 

 from the Ark of the Covenant, on which account I 

 have made inquiries from different persons learned 



in our old Irish annals, if they could give me infor- 

 mation on the subject, but always unsuccessfully. 

 I would therefore be greatly obliged to " C. A. O." 

 if he would put me in the way of getting authentic 

 information about this early immigration of Jews to 

 Ireland. There are records of various immigrations 

 to Ireland given by the different English writers on 

 Ireland and the Irish ; but unfortunately most, if 

 not all of these, are imaginary, and will not bear 

 investigation. On this account any statement of the 

 kind should be carefuljy examined into. I hope 

 there are good proofs of a Jewish immigration, as it 

 would be most interesting to know the origin of 

 these handle -like projections from some of the 

 churches.— The Writer of " Sketches in the West of 

 Ireland." 



" Crabs out or Water."— I notice that in last 

 month's Gossip there is a paragraph on " Crabs 

 out of Water." A curious instance of how long 

 crabs can live out of water came under my notice a 

 short time ago. A fisherman having to remove his 

 hut, which stood about a hundred yards from high- 

 water mark, discovered hidden beneath the flooring 

 and the beach a crab {Carcinus mcenas) in what 

 appeared to be a very healthy state, for it made off 

 at a most rapid pace to an adjoining building. On 

 inquiring I lound that none of the fishermen had 

 been out crab-fishing for three weeks. It would, 

 therefore, seem as though this crab had either lived 

 beneath this hut for so long, or that it must have 

 found its way there after having been thrown up by 

 a storm. I ought to state that under the hut there 

 was a quantity of damp seaweed, &c, which might 

 have supplied it with the necessary quantity of 

 moisture for its gills. — C. P. 0. 



On the Tadpoles op Newts, &c. — Your cor- 

 respondent " G. S.," in the November number of 

 Science-Gossip, says that he has never reared the 

 tadpoles of newts. As I have done so, I write these 

 remarks for the benefit of " G. S.," and any one else 

 who chooses to read them. I one day set out, armed 

 with a pickle-bottle and net, to a pond where I had 

 seen some (as 1 thought) frog tadpoles just hatching 

 out from the spawn; but these afterwards turned 

 out to be the tadpoles of the Triton aqmticus, the 

 common smooth newt, or askel, as it is called in 

 Shropshire. They were slippery little animals,. and 

 eluded my grasp as if they were oiled; however I 

 procured some at last, and secured them in the 

 bottle. When I got home 1 put them into my 

 aquarium, where, by swimming about in a very lively 

 manner, they soon attracted the notice of puss, who 

 managed somehow or other to catch one or two 

 and gobble them up. In less than a week there 

 appeared two small tubercles, one on each side of 

 the neck (or, at least, where the neck ought to be, 

 for it was hard to say where the head ended). 

 These grew very soon into a pair of front legs, 

 which were followed, about a fortnight afterwards, 

 by the appearance ot the back legs. Up to this 

 time the tadpoles possessed external gills, consist- 

 ing of three branchial processes on each side of the 

 head. These were visiole to the beginning of Sep- 

 tember, and were gradually absorbed into the animal, 

 but were not dropped off. The Rev. J. G. Wood 

 says that the newt always wraps its spawn in the 

 leaf of some water-plant. Now, this is certainly 

 not always the case, as I have frequently found the 

 spawn in the ground under water, partly covered 

 with clay, but peeping out here and there from its 

 covering. I have reared both frogs aud toads, also, 

 from the spawn ; and I think that the following are 



