ON THE SHELL-BEARING DEPOSITS AT CLAVA, AND OTHER PLACES. 511 



A Note has also been received from Mr. P. F. Kendall, who was 

 unfortunately prevented from visiting the excavation, but who examined 

 a sample of the shelly clay from the ' main pit.* 



' I have examined a portion of the silty clay sent, and so far have 

 found a large number (relatively) of fry of Nucula or Leda, several small 

 (almost to be called fry) Littorinas, probably L. littorea, and several 

 Foraminifera and Ostracoda. The condition of the specimens is perfect, 

 and, judging from that alone, I should be disposed to say that the silt is — 

 though not necessarily in situ — a portion of a sea-bottom. I do not give 

 any positive opinion, but that is my impression.' 



' I say not necessarily in situ, and without an opportunity of seeing 

 the section, I am indisposed to pronounce a more decided opinion. 

 Apart, however, from the character of the matrix and contents, the 

 general facts connected with the locality, the uniqueness of the deposit, 

 and its limited extent are, in my judgment, strongly against the suppo- 

 sition of its being in place ; and masses of sea-bottom, with perfectly 

 preserved shells and microzoa, are known to have been carried by land-ice 

 to considerable distances.' 



P. F. K. 



VII. Summary of the Evidence and General Conclusions. 



1. The highest part of the shelly clay in the ' main pit ' is 503^ feet 

 above sea-level. The deposit is 16 feet thick in that section, and appears 

 to be continuous for a distance of at least 190 yards in a well-nigh hori- 

 zontal position. 



2. It contains a small proportion of stones, usually well-rounded, and 

 chiefly near the base, varying considerably in relative proportion from 

 those in the overlying boulder clay and underlying gravel. Amongst 

 them is a small block of Jurassic grit ; the nearest point where such 

 rocks occur in situ is about twelve miles due north of Clava, near the 

 Sutors of Cromarty. 



3. The shells are chiefly shallow-water species ; some might have 

 lived at depths varying from 15 to 20 fathoms or in shallower water 

 nearer the shore, but the majority are littoral forms. Though the fauna 

 is not intensely Arctic, it implies colder conditions than the present, 

 there being a considerable number of Arctic species common in the 

 Glacial beds in the west of Scotland. The variety of shells is limited, 

 and there is an absence of certain maiine organisms, often plentiful in 

 those beds. 



4. The shells on the whole are remarkably well preserved, many 

 retaining their epidermis. They are neither rubbed nor striated, differing 

 in this last particular from those found in the shelly boulder clay of 

 Caithness and Orkney. 



5. From the assemblage of organic remains and their mode of occur- 

 rence, it would appear that the deposit is a true marine silt, or, in other 

 words, a portion of an ancient sea-bottom. If the deposit is not in situ, 

 then we can only suppose it must have been transported in mass to its 

 present position. 



6. The direction of the ice-flow in the surrounding district, as proved 

 by the striae and transport of boulders, seems to point to the conclusion 

 that the laud-ice which passed over Clava did not previously cross any 



