556 Zoological Society. 



{Penelope pileatn of Wagler), and also a skin of the same species 

 from Para. He had Ukewise forwarded some specimens of Marine 

 Corallines and other Zoophytes, recently obtained during the prose- 

 cution of a coral fishery on the coast of Barbary. 



A letter from J. Wardrop, Esq., dated Oct. 29, 1840, was next 

 read. It refers to a Fowl brought by W. Wardrop, Esq., from the 

 Island of Lemurs, and presented to the Society. In this Fowl the 

 spur had been removed from its proper place, and engrafted on the 

 head. The letter moreover states, that the natives of the island men- 

 tioned often cause the spurs of the cock bird to grow upon its head, 

 and the comb upon its legs. 



The following paper, by G. Gulliver, Esq., F.R.S., entitled "Ob- 

 servations on the Blood Corpuscles of the CrocodiUdtE," was read. 



" According to the observations of MM. Prevost and Dumas, Wag- 

 ner, Schultz, and others, the long diameter of the oval blood coqjus- 

 cles of the vertebrate animals is never more than one and a half or 

 twice the short diameter ; and M. Mandl states that this accords with 

 his experience, except in regard to the blood coq^uscles of the Cro- 

 codilidcE, of which he says that the long diameter is between two or 

 three times greater than the short diameter. 



" M. Mandl's observations are published in the Annates des Sciences 

 Naturelles, seconde serie, tome xii., in which the following remarks 

 occur: 'En prenant dans les globules des chameaux*, oiseaux, rep- 

 tiles et poissons, le petit diamfetre pour unite, le grand varie entre 

 li a 2 ; on en rencontre une exception dans les Crocodiliens, dont le 

 grand diamfetre est 2 a 3 fois plus grand que le petit.' 



" It appears that this conclusion was deduced from an examination 

 of the blood of a single species only, the Crocodilus Lucius of Cuvier. 



" In a short paper 'On the Blood Coqjuscles of the Snowy Owl 

 and Passenger Pigeon,' read before the Society on the 9th of June, 

 1840, I showed that the corjiuscles of these birds, particidarly of the 

 former, were so very long, in relation to their breadth, as to present 

 a peculiarity in this respect which I had not seen in the corpuscles of 

 any other vertebrate animal ; and, however singular it might appear, 

 it was showTi in the same communication that the blood- discs might 

 differ remarkably in two nearly allied species of the same genus. 

 Hence it will not appear surprising that I have failed to find the same 

 peculiarity in the figure of the blood corjiuscles of two other species 

 of the Crocodilidce, as M. Mandl did in the Crocodilus Lucius. In the 

 following measurements the common-sized corpuscles are first noted, 

 then those of extremely small and large dimensions, and lastly the 

 average deduced from a computation of the whole ; and they are all 

 expressed in fractional parts of an EngUsh inch. 



• M. Mandl says in a note, " Nous avons examine le sang du Dromadaire, 

 de I'Alpaca, et du Chameau." I may add that I have examined the blood 

 of the Vicugna and Giiawaco, and found their corpuscles also of an oval shape, 

 thus completing the history of the singular red particles of the CameIid(B. 

 Sec 'Dublin Med. Press,' November 27, 1839, and 'Trans, of the Royal 

 Med. and Chiiurgical Society,' vol. 23. 



