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will be readily seen by the three subjects — bird, mammal, and amphibian 

 — taken to produce the same result, viz., a perfect skin in a preserved 

 and life-like condition, will require, owing to their dissimilarity of 

 character and structure, a different modus operandi. A freshly killed frog 

 was taken, and, instead of making an incision in the abdomen, as in the 

 case of the rabbit, or on the breast or side, as in the rook, the whole 

 of the interior was extracted through the mouth. This may seem rather 

 a novel procedure, but when we consider the very wide oral aperture of 

 the frog and its very contractile skin the advantage of this mode will 

 be readily apparent — that of leaving the entire skin intact. A sharp 

 pair of dissecting scissors are carefully put down the mouth. First, the 

 vertebra is severed, then the attachments of the limbs, and bit by bit the 

 whole interior is got out, leaving the collapsed skin, which is filled with 

 powdered plaster of Paris. The frog is then put into its natural shape 

 and immersed in water, when, of course, the plaster inside sets firmly. 

 By this method the specimens are permanently, with life-like appearance, 

 preserved. The colour, too, is by this process retained. 



Meeting -held in the Club's Room, Municipal Buildings, October 28th, 

 1889. John Stubbins, F.G.S., F.E.M.S. (Vice-President), in the chair. 



ALBINO BIRDS. 

 J. B. HALL. 



Mr. Hall pointed out that he brought the subject forward not with the 



idea of dilating on any particular theory, but rather of laying before the 



society a number of facts and observations collected during the last six 



years. He stated that there are two conditions in birds commonly classed 



under the term albinism ; one, which may be called the complete form, 



which probably does not differ from true congenital albinism in mammals, 



and another, the incomplete form in which only single feathers or groups 



of feathers are affected, this last form being possibly the result or rather 



the sequence of disease. That these two forms, whatever be their origin, 



are distinct and separate is shown by the fact that the complete has been 



observed in young birds still in the nest and still acquiring their first 



plumage, and that the incomplete has been observed to remain unchanged 



through several years without varying in the slightest degree. In manjmals, 



true albinism is well known, but with the exception of domesticated 



animals there is no form which corresponds to the incomplete form in birds. 



There is, however, a similar condition produced in mammals by certain 



diseases, and the analogy points rather to the incomplete form in birds 



being a condition of the same kind. The nature of the disease producing 



this result it is impossible to determine until more evidence has been 



collected, but three morbid conditions may here be mentioned as showing 



the close analogy existing between the two conditions in the bird and the 



mammal. Parasite affections of the skin in mammals produces white 

 c 



