416 Viscount Walden on new Sjjecies of 



cirri of the Holotliuridas, the dorsal tubuli of the Asteridfe, 

 and the ambulacral systems of canals of the class generally. 

 In no division of the animal kingdom do the respiratory 

 organs occupy a larger proportion of the whole bulk than 

 they do in the Echinodennata. The great size which the 

 convoluted plate attains in some of the Crinoids is therefore 

 rather more in favour of its being a respiratory than a digestive 

 organ. 



Professor Wyville Thomson says that, inside of the cavity 

 of the stomach of the recent Crinoid Antedon i-osaceus, there 

 is a spiral series of glandular folds, which he supposes to be a 

 rudimentary liver (Phil. Trans. E,. S. 1865, p. 525). It is 

 barely possible that the convoluted plate may represent this 

 organ. At present I think it does not. 



I believe that the reason why the convoluted plate attained 

 a greater proportional size in the palaeozoic Crinoids tlian do 

 the sand-canals of the recent Echinoderms, is that the function 

 of the system of canals (of which they are all appendages) was 

 at first mostly respiratory, Avhereas in the greater number of 

 the existing groups it is more or less prehensive or locomotive, 

 or both. 



[To be continued.] 



XLVIII. — Descrtjytions of some new Species of Birds from 

 Southern Asia. By Arthur, Viscount Walden, P.Z.S. &c. 



Geocichla layardi^ n. sp. 



The Geocichla of Ceylon is most nearly allied to O. citrina^ 

 (Lath.), of Northern and Central India, and not, as might 

 have been expected, to G. cyanota, (J. & S.), of Malabar. 

 From Latham's bird it is to be readily distinguished by the 

 much deeper orange of the head and nape, these parts being 

 of the same dark shade of orange-brown characteristic of G. 

 ruhecula^ Gould, ex Java. ( )n the under sm-face the orange 

 tints are brighter and richer than in citrina^ yet not nearly so 

 dark as in G. ruhecula ; the blue-grey portion of the plu- 

 mage is likewise darker than in G. citrina^ but not so dark as 

 in G. ridjecula. In the distribution of the white plumage the 

 three species resemble each other ; they appear, along with 

 G. ruhigijiosa, Miiller, ex Timor, to form a small natural sec- 

 tion. Wing 42- inches, bill ^. 



Described from a single Ceylon exani])le, and which is 

 marked by the collector as " rare." 



