422 Correspondence — Mr. G. A. Lehour. 



which, to many palEeontologists was far from being impassable, long 

 before the discoveries just mentioned. The amphicoelous character 

 of the vertebrae of Ichthyornis presents another most remarkable 

 peculiarity, which is also of high significance. I hear rumours of 

 the discovery of another Archceopteryx in the Solenhofen Slates, 

 which is said to present the head in a much more complete condition 

 than that in which it occurs on the magnificent slab now in the British 

 Museum. As yet, I believe, the jaws have not had the matrix 

 removed from them ; but should they prove to be armed with teeth, 

 it will to me be a cause of satisfaction rather than surprise, as con- 

 firming an opinion which some fifteen years ago ^ I ventured to 

 express, that this remarkable creature may have been endowed with 

 teeth, either in lieu of or combined with a beak. 



I must not, however, detain you longer with any of these general 

 remarks, which are, moreover, becoming somewhat egotistic, but 

 will now proceed to the business of this Section, in which I hope 

 that more than one paper of great value and interest will be forth- 

 comino:. 



coi?,ie;Es:poisrx)EisroE. 



THE MONTE GENEROSO BEDS. 



Sir, — The French Geologist who supplied information to your 

 correspondent, the Eev. E. M. Cole, respecting the age of these beds 

 (Geol. Mag., Decade II. VoL V. p. 378), provided him with an 

 order of succession which has been well known for many years. 

 But if the divisions and their relative positions be clear enough, 

 their correlation with members of the Mesozoic series in England is 

 fraught with considerable difficulty. 



The Como deposits in question include all the representatives of 

 the Lias and Oolites and something more. Taking them one by one 

 in descending order, as given by Mr. Cole's informant, we have : 



1. Maj clique : A white compact limestone, the celebrated Majolica 



marble of the Italians. This must not be mistaken for the very 

 similar Biancone, which was for a long time confounded with it, 

 but which is now known to be of Neocomian age, and conse- 

 quently newer than the Majolica. The latter is not only like 

 Chalk in appearance, but is, like it, also characterized by the 

 presence of flints in nodules and bands ; it is often dolomitic and 

 contains but few fossils, principally Trigonellites and rarely 

 Ammonites. 



2. Calcaire rouge : The Calcare 7-osso ammonitifero of Lombardy, not 



altogether the representative of the division which goes by that 

 name in the Apuan Alps. This red deposit teems with Ammo- 

 nites of species which, to the confusion of the paleeontologist, 

 are elsewhere characteristic of various horizons from the Lower 

 Lias to the Upper Oolite. 



' Nat. Hist. Eev., vol. v. p. 421. According to Dr. Haberlein, the possessor of 

 the second specimen, the jaws are armed ivith teeth ! thus confirming Dr. John Evans's 

 opinion founded on an examination of the specimen preserved in the British Museum ; 

 where, on the slab of stone which contains it, a small detached jaw with teeth is to 

 be seen lying. — Edit. Geol. Mag. 



