5758 Fishes. — Mollusks. 



Note on the Little Auk (Una alle) appearing on the Norfolk Coast in Summer. — 

 I have now in my possession a specimen of this bird, with the perfect black throat of 

 the summer plumage, which was shot at Wells, on this coast, about the 26th of May. 

 This bird, which was shown me in the flesh, was shot from the beach whilst skimming 

 rapidly over the waves close in shore, and was covered with sand when brought to me. 

 Mr. Yarrell says of this species, " It is only a winter visitor to the British Islands, and 

 is more frequently met with among those of Orkney and Shetland than further South.'' 

 It is also known to frequent and breed in such high northern regions that the occur- 

 rence of this single specimen on our coast at such a time is not perhaps unworthy of 

 record. Scarcely an autumn or winter passes without a few being taken in various 

 parts of Norfolk ; but these may be reckoned rather as accidental than regular visitants, 

 driven from their proper course by storms ; and thus not only drifted on to our coasts, 

 but carried sometimes for miles inland, till they fall exhausted in the streets of our 

 towns and villages. During the last winter, after the high winds which prevailed at 

 different times, many of these birds were picked up, and one was taken alive in a yard 

 in the centre of this city. All these have of course the white or grayish white throat 

 peculiar to the winter season ; but I am not aware of any previous instanpe of the 

 little auk visiting us in summer. — H. Stevenson ; Norwich, July 6, 1857. 



The Eye of the Carp turns on its Axis. — In watching a small carp seeking food 

 alternately at tbe surface and the bottom of my fresh-water aquarium, I remarked the 

 eye turns upon its axis, and does not partake of the inclination of the body. The 

 same movement may be seen in the human eye by inclining the head towards either 

 shoulder before a looking-glass. Thus the images of earih and sky fall upon the same 

 portions of the retina in all ordinary positions of the head. May not the reversal of 

 these conditions account in some measure for the effects noticed in viewing a land- 

 scape with the head inverted and looking between the legs, effects which are usually 

 imputed to the additional flow of blood to the head? — George Guyon ; June 15, 1857. 



Giant Specimens of Unio tumidus and U. pictorum. — I have met with these 

 Uniones in two ponds in this neighbourhood, situated in the parishes of Fleckney and 

 Wistow, of a size which I believe to be wholly unexampled. Forbes and Hanley write 

 of Unio tumidus, "A fine specimen measured three inches in length, and more than 

 half that in breadth at the widest part ;" and of U. pictorum they remark that " a large 

 individual measured full three inches in length, and nearly an inch and a half in 

 breadth." In the following table I give the dimensions and weights of Wistow and 

 Fleckney specimens, and have added those of my finest examples from other localities 

 for the sake of comparison. Number 5 is a dwarf variety of U. tumidus, from the 

 Cherwell, Oxford, where it rarely, if ever, attains a size larger than that of this speci- 

 men. The difference between the Uniones of this neighbourhood and others will be 

 seen more remarkably by a comparison of their weights than by that of their measure- 

 ments. The sura total of the weights of 3, 4, 8 and 9, it will be observed, only 



