156 Scientific Intelligence. 



and the stones in the till, clearly indicate that this island win 



glaciated hy a mass of ire moving from east to west. The proofs 

 of continental glaciation, which are comparatively clear in the 

 north, are obscured in a great measure in the main island l»v the 

 effects of a local ice-sheet. The nature of the bowlder clav, as well 

 as the trend of the striae in various localities, show that the move- 

 ment of this local sheet was influenced by the general features of 

 the country. In addition to these markings, however, others were 

 found which could not have been produced by ice shedding off the 

 land in the ordinary way. These cross the" island, regardless of 

 its physical features, and are often at right angles to the newer 

 set. Lastly, the wide distribution of morainic matter wiili groups 

 of moraines indicate the gradual disappearance of the local ice- 

 sheet and the presence of small glaciers, where the ground pre- 

 sented favorable conditions for their development, 



The islands are dotted over with small lochs; the most of these 

 lie in peat or drift, while others occupy true rock basins The 

 singular absence oi marine terraces ought not to escape notice, as 

 hearing on the recent geological history of these islands, since the 

 voes or sea-lochs are admirably adapted for their preservation. 



These observations will be described in detail in a forthcoming 

 paper before the Geological Society. John Horne. 



— Xnture. Dec. 14, 1876. 



4. Xote on the relations of Balnnm />■'/■, llnims of the < •.iliformn 

 31 ;,„■,„,: ; hy T. A. Conrad. (From a letter to J. D. Dana, dated 

 Philadelphia, Dec. 4, 1876.)— Some time ago I wrote you for 

 your opinion of the propriety of classing linlmms KstrelOmns (Ta- 

 mionoma t/r- '.-tn. It seemed so strange to me, 



that a memb, i t t Rn I -• < A u !d b, in Miocene strata, that I 

 have recently studied its characters anew, and find it to be a true 

 linln,,,,*. and I think you will agree with me. if you consult the 

 figure and description of 11. h, ,■;, figured in Darwin's Monograph, 

 pi. 4, fig. 2. In that ii its septa of the precise 



character of JJ. Kstr>lln„ns; besides, the loss of the basis -hows 

 the same structure as other Balani. but the opercular valves are 

 not preserved. Mr. <-obb fulh agrees with mv determination. 



I have also had occasion to restrict the number of genera which 



Thus I eliminate the genus Cw.nl i - t ami. 



it being represented by fdonenrca. I think also that Trigonia 

 died out at the close of the Cretaceous; for, of the many m>< <ies 

 known, none had ribs radiating from the beak, like a ( ,,„/;,<„: 

 and being unknown in Eocene strata; when the allied genus 

 appear- in the Miocene and recent fauna it assumes the radiated 



structure. I also exclude bom th < i.ti istowKth. following 



genera of Vener'nhe : CnlUsia. <nn/»t,ts, Dione, Qrateloupea, 

 <'r<i r t. .urn,,,,,*. i, <;,■., />,, <,„;<i. 3/ercenaria, Venvs, etc., retain- 

 ing ii j Lpf, , / j r ' i, i i \ I> , ojiiis Some 

 •■'"/</, <) siren, A mm, In, SpondyUs, 

 Axinoux, Ikirritella, etc., were continued from Cretaceous strata to 



