56 



and common Gull {Larus canios). The Razorbill perished in extraordinary numbers, being found 

 in the proportion of ten to one of the other species. From information communicated to the 

 Natural-History Society of Glasgow by one or two of the members, it would appear that the 

 mortality had set in about the time of the birds leaving Ailsa Craig and the breeding-places off 

 the coast of Ireland, and that during the few intervening weeks they had probably, from, a 

 diminution or entire absence of their usual food, fallen into a low condition favourable to the 

 development of the disease to which they ultimately succumbed. They were all found much 

 farther up the Firth than usual, as if in search of food, many birds being obtained even at Renfrew 

 and other places, in waters at a distance from the sea. In these situations they darted eagerly 

 at any food which came in their way, rushing at baited hooks on a hand-line, and otherwise 

 exhibiting a tameness more like the result of starvation than actual disease. They were all in 

 a wasted condition, being reduced almost to skin and feathers, and were found dead or dying in 

 thousands over a wide extent of sea, from the mouth of the river Clyde to the Irish coasts, the 

 master of one of the mail steam-packets having reported that he sailed his ship through miles of 

 floating carcases. At a meeting of the same Society, held on 29th November following, my 

 friend Mr. David Robertson read a report on this mortality, in which he gave an apparently 

 satisfactory explanation of the mystery. In this communication it was shown that nothing 

 unusual was observed among the birds until a few days after the storms in the early part of the 

 month of September ; and that they were then in a state bordering upon starvation may be 

 proved from the fact of so many hundreds, even thousands, resorting to estuaries, heedless of 

 danger and contrary to their usual shyness. The testimony of the fishermen at various places 

 showed that the common dog-fish was unusually abundant, while the small herring-fry and other 

 fishes constituting the food of sea-birds had entirely disappeared." 



The specimens figured are an adult male, in full summer dress, and a young bird in its first 

 winter plumage, both being those above described. 



In the preparation of the above article I have examined the following specimens : — 



E Mus. H. E. Dresser. 

 a, b, c, d, e, ad. in summer dress. Greenland (Erichsen). f, 6 . Orkney, May {Dunn), g, pull. Lundy Island, 

 July 1871 {H. Saunders). 



E Mus. E. Eargitt. 

 a, $ . Orkney, January 25th, 1869 {E. H.). b, 6 . Havre, February 3rd, 1875. c, d, ? . Havre, March. 4th, 

 1875 {Pluche). 



M 2 



