FROM THE EDDYSTONE GROUNDS TO START POINT. 44 L 



In the case of many of the species the geographical and bathy metric 

 distribution is noted, and this is followed by an account of the kinds 

 of deposit upon which the species has been obtained by other observers 

 in different localities. In considering the latter records it must be 

 constantly borne in mind that the terms made use of up to the present 

 time (sand, gravel, mud, etc.) have not been employed in the strict and 

 definite sense which has been given to them in the present paper, and 

 there has been much obvious confusion in their use. 



There is, in particular, one source of error which has probably 

 operated very frequently, and by which I was myself several times 

 misled until actual samples of the deposits were obtained with the 

 canvas dredge. Dead shells of bivalve molluscs are frequently taken 

 with the two valves united and closed, which, on being opened, are 

 found to be filled with fine mud or muddy sand. No doubt this has 

 often been supposed to indicate that the deposit is mud or fine muddy 

 sand. Such, however, is by no means the case, as shells so filled may 

 be taken on all grounds where a certain proportion of nmd is mixed 

 with coarser material, and I have found them particularly numerous on 

 the coarse muddy or sandy gravels. It is very probable that this 

 circumstance has led to many animals being recorded as living on mud, 

 when in reality the bottom-deposit from vt^hich they were taken was a 

 muddy gravel or coarse sand. 



The explanation of the fact that the shells are filled with mud 

 appears to be that when the bottom is disturbed, either by wave 

 action or by the movements of animals, the mud in the deposit is 

 stirred up, and the muddy water, entering the shells by a narrow 

 aperture, deposits its solid particles, which gradually accumulate 

 inside the shells. 



In addition to the error which has probably been made in describing 

 as mud the deposit on grounds where such shells have been dredged, 

 the term sand has clearly been used in a very general sense to include 

 much coarser deposits than those included in the present paper under 

 that head. 



FORAMINIFERA. 



[^Nomenclature: — Brady, No. 13.] 



Tritncaivlina lohatula. This species is abundant on all hydroid 



grounds, whether the prevailing species is Sertulardla Gayi, Halecium 



halecimim, or Sertalaria abiclina, and on the grounds where Cellaria is 



plentiful. It is found clinging in numbers to the stems of the zoophytes. 



Foraminifera were also found in large numbers in the dried samples 

 of the bottom - deposit. The skeletons, many of which doubtless 



