288 Correspondence — Dr. A. H. Foord. 



hj'ponomic sinus ; the spines (similar in structure in the two species) 

 are nearly straiglit, and slightly inclined downwards. The septa are 

 not numerous. In the Russian species, on the other hand, the shell 

 is more slowly expanding, the hyponomic sinus small and in- 

 conspicuous, the spines slightly curved, and inclined upwards. The 

 septa, only faintly indicated on the larger of the two specimens 

 figured, are more numerous than in the Irish species. The 

 siphuncle, not seen in A. hispinosus, is in N. cornutus sub- 

 central, and inclined towards the inner margin of the shell ; this is 

 the case at least in the smaller of the specimens figured, which also 

 shows in a section the slow expansion of the whorls. 



The discovery of the Irish Carboniferous species shows that this 

 peculiar type of Nautiloid had a wide geographical range, while its 

 appearance in the Permian of Russia extends its range in time. 



The work in which JV^. cornutus is described seems to have been 

 generally overlooked, as I have seen no reference to it even in books 

 and papers dealing exclusively with Carboniferous or Permo- 

 Carboniferous fossils. 



My thanks are due to you, Sir, for your courtesy in allowing me 

 to see Professor Blake's letter, thus enabling me to compare and 

 comment upon the two species ; and to Professor Blake science is 

 indebted for having drawn attention to this " first cousin " of 

 A. hispinosus. Arthur H. Foorb. 



Dublin, May 13, 1897. 



P.S. — With reference to Mr. Sherborn's letter which you have 

 also kindly granted me the privilege of perusing, I can only say that 

 I did not consider that the private distribution of a few copies of 

 a paper could fairly constitute publication. The fact, however, 

 seems to be that when once a paper has left its author's hands, and 

 can therefore be quoted, it must be considered as published. I am 

 obliged to Mr. Sherborn for pointing this out to me ; I could have 

 no better authority to guide me in the matter than his. — A. H. F. 



nynisGiBXjXjj^isriEOTJS. 



"The Distribution of Drift in Ireland in its relation to Agricul- 

 ture " is the title of a paper by Mr. J. R. Kilroe (Proc. Royal 

 Dublin Soc, ser. 2, vol. viii, 1897, pp. 421-431 : published 

 separately, price Gd.). It is accompanied by a geological map, 

 printed in colours to show the areas where the more solid rocks 

 appear at the surface, the large tracts (two-thirds or more of the 

 country) which are covered by various drift deposits being left 

 blank. As the author rightly points out, a map that would meet 

 the requirements of the agriculturist must show, on a fairly large 

 scale, the distribution of the subsoils, and indicate not only the 

 materials of which they are composed, but their thicknesses at 

 different localities, and in some cases the subjacent strata. This 

 could be indicated by colours, letters, and numbers ; and the author's 

 aim is to make suggestions towards this object. He appends a table 

 showing the nature of soils, subsoils, and boulder-clays in various 

 parts of Ireland. 



