150 Proceedings of Philosophical Societies. [Feb. 



Schehallien, of Piazzi at Palermo, of Mudge in England in 1802, 

 and of Lambton in Hindostan in 1805. The Westbury obser- 

 vations, he remarks, differ too much from the Greenwich to be 

 available in this question ; and those of Mechain are opposed by 

 others made with better instruments. Mr. Pond has diminished 

 the quantities in Dr. Brinkley's Catalogue, by applying Brad- 

 ley's refraction, while he leaves M. Bessel's in their original 

 form ; and is thus enabled to place his own as means between 

 them : to which mode of correction, however, Dr. Brinkley 

 strongly objects. The question of Parallax, Dr. B. considers, 

 is still quite open for discussion ; but its consideration he defers 

 for the present. Various tables are annexed to the paper, in 

 illustration of the statements it contains. 



A paper was likewise communicated, " On the Figure requi- 

 site to maintain the Equilibrium of a homogeneous fluid Mass 

 that revolves upon an Axis ; " by James Ivory, Esq. MA. 

 FRS. 



The Society then adjourned over the Christmas vacation, to 

 meet again on Thursday the 8th of January. 



Jan. 8. — At this meeting, Anthony M. R. Story, Esq. was 

 admitted a Fellow ; and the reading was commenced of a paper, 

 entitled, " Observations on the Positions and Distances of 

 Three Hundred and Eighty Double and Triple Fixed Stars, made 

 in the Years 1821, 1822, and 1823;" by J. F. W. Herschel, 

 Esq. FRS. and J. South, Esq. FRS. 



LINNEAN SOCIETY. 



The meetings of this Society were resumed on the 4th of 

 November. Among the presents then on the table were speci- 

 mens of eighty-five species of birds sent from India, by Major- 

 Gen. T. Hardwicke, FRS. and FLS., comprising many rare and 

 several new species ; and with them was a curious species of 

 musk rat ; and also the head of Antilope Quadricornis, the Chi- 

 kara of Bengal, a notice of Gen. Hardwicke's description of 

 which, read before the Society on the 17th of June last, will be 

 found in the Annals for the succeeding August. 



The following communications were read : 



" A Description of the Swallow-tailed Falcon, Falcofurcatus, 

 Linn, taken near Havves, in Wensley Dale, Yorkshire, in 1805 ;" 

 and, " A Description of a Bird, supposed to be the Rallus 

 pusillus of Latham, shot at the same place in 1807 ;" by W. Fo- 

 thergill, Esq. communicated by Dr. Sims, FLS. 



Observations on the Genus Onchidium of Buchanan, with a 

 Description of a new Species ; by the Rev. Lansdown Guilding, 

 FLS. 



In this paper Mr. Guilding gives an improved generic charac- 

 ter of Onchidium ; class Mollusca: ord. Cephala; div. Ga$tero~ 

 poda : " Corpus oblongum, repens, subtus planum. Penula car- 

 nosa pedem totum tegens. Os anticum, longitudinale. Anus pos- 

 ticus, infra, Tentacula duo retractilia. Oculi terminales." He 



