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HARDWICKE'S SCIENCE-GOSSIP. 



and is occasionally scarcely distinguishable from 

 coarse granite. In colour it is a bright brick red, inter- 

 mingled here and there with white quartz. Few 

 distinct crystals of any of the constituent minerals 

 can be obtained, and of these the majority are mica 

 crystals in the rhombohedral form. Garnets occur 

 frequently in the mica, though lacking the perfect 

 form so frequently exhibited in the later schists. 



If a ramble to the southern Sutor be made, the 

 student will be rewarded by splendid exposures, and 

 by a lessson on the Gneiss rocks which will amply 

 repay him for his trouble. He must however, be 

 prepared for rough climbing, while a firm foot and a 

 steady nerve are perfect necessities for this somewhat 

 hazardous journey. He must be careful also to 

 choose his time well, so as to reach the Cromarty 

 side of the cliff before low water. He may then 

 spend two or three hours examining the rocks, the 

 cliff at the base being fairly accessible, but soon 

 after the tide has turned he must, in order to avoid 

 any disagreeable consequences, proceed as quickly as 

 possible to the eastern extremity or retrace his steps. 

 Failing this he may find himself perched on some 

 rock from which he cannot proceed upwards, and 

 from which he dare not descend. 



The beach on both sides of Cromarty is literally 

 paved with schists of various kinds, which have been 

 rounded and thrown on to the shore. An inspection 

 of these will give the student a good idea of the 

 composition of the Primary rocks in and contiguous 

 to the Firth of Cromarty. 



The Old Red Sandstone deposits of Cromarty are 

 sure to be examined with double interest by any 

 geologist who visits the place. These are well 

 exposed on both sides of Cromarty, and within a mile 

 from the town. They comprise some of the lowest 

 beds of the formation, being as it were, the very 

 foundation of the system. The exposures of the 

 Cromarty Firth side of the town consist of dark red 

 rocks, very friable, and coarse in texture. They are 

 unfossiliferous, and consequently need little descrip- 

 tion. On the Moray Firth side of the town a higher 

 bed occurs, but it is not accessible except at very low 

 water. When circumstances are favourable a really 

 pleasant and interesting time maybe spent, and fairly 

 good specimens of the various fossil ganoid fishes 

 may be obtained. The remains are enclosed in lime- 

 stone nodules which emit the usual odour on 

 being struck by the hammer. A large number of 

 these nodules may be collected from the rusty 

 coloured matrix of sandstone in a short time, and 

 most will be found to contain some specimen of 

 fossil-fish more or less perfect. Amongst the 

 specimens so likely to be found we mention the follow- 

 ing as characteristic : — Diplacanthus striatus, Dipterus 

 macrolepidotus, Coccostcus decipiens and cuspidatus, 

 Climatius scutiger, Cephalaspis (sp.), Pterichthys 

 Milleri, oblongus, and latus, Glyptokpis leptopterus, 

 Cheirolepis Trailli, Asterolepis (sp.). 



The Dipterus, Pterichthys, Diplacanthus, and 

 Asterolepis specimens are usually fairly good, while 

 of the others probably only detached scales and 

 plates will be got. Much of the information we have 

 concerning these early ganoids is due to the 

 enthusiasm and patient energy of Dr. R. H. 

 Traquair, Edin., who is probably the best living 

 authority on the Palaeontology of Fishes. No shell 

 remains are found in these beds, but not unfrequently 

 imperfect impressions of Fucoids (Zosterites, etc.,) 

 may be brought to light. After a very severe storm 

 or an exceptionally high tide, this particular spot, 

 about mid-way, between the town and the southern 

 Sutor is strewn with the nodules containing the 

 above remains, and the geologist who happens to be 

 staying in the district at such a time will do well to 

 take advantage of such an opportunity for adding to 

 and enriching his cabinets. 



The Liassic formation is represented at and near 

 Cromarty by some of its upper beds. Those at 

 Cromarty lie under the water just beyond, and east 

 of the quay, but occasionally the limestone nodules 

 and other rock specimens containing organic remains 

 are dislodged by the water and thrown on to the 

 shore. The best localities in the neighbourhood for 

 the study of the formation are Eathie shore (three 

 miles from Cromarty ,on the Fortrose road), and 

 between Shandwick and Barachie on the coast of 

 Easter Ross, about six miles north-east of Nigg 

 Ferry. At Eathie the upper lias is exposed partly in 

 nodulous limestone, and partly in a series of 

 laminiferous beds. The nodules contain the best 

 fossils, though, as usual, they are very difficult to 

 extract. The perfect specimens when obtained are 

 exceedingly beautiful. Ammonites biplex and 

 ornatus occur, varying in size from half an inch to 

 five inches in diameter ; Belemnites abbreviatus, 

 spicularis, and obeliscus, may be obtained (usually 

 broken) in the shaly beds. These latter also contain 

 thousands of Ammonites, generally crushed beyond 

 identification. Lignite is very common in the lime- 

 stones, and occasionally small scales, teeth and jaws 

 of fish may be observed side by side with small 

 specimens of Pecten, Gryphrea, etc. 



The rambler will readily find the fossiliferous 

 bands if he keeps the main road between Cromarty 

 and Fortrose, only descending on to the shore (by a 

 circuitous path branching off to the left) after he has 

 reached the very summit of Eathie Hill. 



At Shandwick the Middle Lias is exposed, and good 

 fossils may be got by thoroughly and carefully 

 examining the small promontory locally known as 

 " West Point." The varieties do not appear to be 

 numerous, and probably the most characteristic are 

 A. perarmatus, B. canaliculars, Rhynconella lineata 

 and Gryphcca iticurva. 



There are other places of geologi cal interest which 

 might be mentioned, but for the ordinary holiday 

 tourist those already described will probably suffice. 



