PROCEEDINGS OF THE BRITISH ASSOCIATION. 429 



the Channel islands : Anemone nemorosa, Bromus asper, Campanula (none 

 of the genus), Hypericum hirsutum, Listera ovata, Betula alba, Caltka pa- 

 lustris, Habenaria chloranthus, Helianthemum vulgare, Juncus glaucus, 

 Of those common in England and rare in the Channel islands he had found 

 Cardamine pratensis, Lamium album, Primula veris, Ranunculus ficaria, 

 Mercurialis perennis. Of those rare in England and common in the islands, he 

 had met with Orobanche ccerulea, Scrophularia scorodonia, Lotus hispidus, 

 Erodium moschatum, Iris foetidissimus, &c. 



Mr. Allis then read a paper " On the Sclerotic Bones of the Eyes of Birds^ 

 and Reptiles." He began by adverting to the little attention this subject had 

 received from naturalists and comparative anatomists. When he commenced 

 his investigations he had no idea of the difference in size, form, number, and 

 texture these peculiar organs presented. He then made quotations from Cuvier, 

 Blumenbach, Yarrell, Carus, and Buckland on this subject ; and having 

 demonstrated the points of agreement and difference between his observations and 

 those of the authors above quoted, he stated that " the shape of the individual 

 bones is so various, that it cannot be given in any general terms ; the external 

 edge of the bones is, in most instances, beautifully serrated, but the serration is 

 not visible in the bony ring : this serration being generally destroyed by the 

 process of boiling that is necessary to their preservation. The rings generally 

 overlap each other, there being a depression on the under side of one bone, and 

 a precisely corresponding one on the upper side of its fellow ; so that when over- 

 lapping each other they present nearly an even surface, having one bone with both 

 depressions on its inner surface, and forming an interior key to the arch, another, 

 having two depressions externally, and forming an exterior key. They form a 

 defence and protection to the eye, and those birds which are pugnacious, or have 

 a peculiarly rapid flight, or vary their attitude in flying, &c, have the sclerotic 

 rings of larger size and more convex form, and are of greater strength ; the same 

 remark holds good with respect to water-birds. Another use of these bones is, 

 altering the convexity of the cornea, as mentioned by Dr. Buckland." He then 

 exhibited a great number of specimens of these bones, and observed that in the 

 Eagles and Vultures they were strong and large, and varied in number from 

 fourteen to sixteen; in Owls soft and porous, and not hard, as Cuvier had 

 stated ; in the Gallinidce the number varied from thirteen to seventeen ; in the 

 Columbidce they were small and feeble ; in the Ostrich tribe they were large ; 

 in the Grallce small and feeble ; in the Scansores the same, and twelve or thirteen 

 in number ; in the Swimmers they were weak and small, and from twelve to 

 sixteen in number ; in Divers strong and large, and twelve to fifteen in number ; 

 in the Passerince they varied considerably, but were generally weak ; in Reptiles 

 they varied considerably in number, shape, and size. 

 No. 14, Vol. II. 3 L 



