4 2 8 ^ Usee Uane.ous. 



l>iit thoy ore now completely transformed into carbonate of lime. 

 I'hombohcdra of calcite appear to liavc complett-d their growth as 

 readily within the spicule as outside it, and the final result of the 

 corrosion is to entirely re])lace the opal of the spicule by a congeries 

 of inimite crystals of calcite. As tlie crystals may have begun their 

 growth outside the spicule, the latter rarely preserves its charac- 

 teristic regular outlines. The crystals being frequently bounded by 

 impurities of the limestone, the spicules are often as clearly defined 

 as corresponding structures in the Chalk. 



MISCELLANEOUS. 



A Note on the Date of the Parta of' Tluinholdt and Bonpland^s 

 Voi/itf/e : Obnervations de Zoologie.' 



This book was issued in livraisoris as follows : — 



Vol. I., livr. 1, pp. 1-46 (& 47, 48), 1805, forming pp. 1-2.') of 2ud issue. 



•2, -104, 1^07, „ 2(1-64 



y, -196, 1807, „ 6.3-126 



4, -293, 1809, „ 1 27-200 & 253-2.59 of 



2nd issue. 

 5&G, -412, 1809, „ 261-297 & 201-2.52 & 



298-309 of 2nd 

 issue. 



A break then occurred until 1812, when livraison 7 Avas issued, 

 with the fcllowing " Avis " on a loose slip of paper : — " Avec cette 

 Livraison, qui terraiiiera le premier volume des Observations de 

 Zoologie et d'Anatomie comparee, on fournit aux Abonnes un 

 iiouveau texte pour la totalite de ce volume. On a cru devoir faire 

 ce sacrifice, afin que cet ouvrage ressemblat, pour le caractero et le 

 papier, a toutes les autres parties du Voyage de M. de Humboldt. 

 Les Acquereurs pourront faire relier ce volume ; ils rendront tout 

 le texte des livraisons precedentes, donts il ne conserveront que les 

 planches." Fortunately for nomenclature the British Museum 

 (Natural History) secured some years ago a parcel of odd parts, 

 which prove to be a complete set of the first issue ; these are 

 jiroperly cared for, and are of considerable interest. 



The completion of the work dates as follows : — 



Livr. 7, pp. 00.5-368 (with reprint of pp. 1-412 of 1st issue, forming 

 pp. 1-.309 of 2nd issue), 1812 (T.P. dated 1811). 

 V.l. IT., livr. 8, 1-64, 1813. 



9, -96, 1813. 



10, -144, 1817. 



11, \ 004 1821. 



12, J —^'1821. 



13, -256, 1827. 



14, -352, 1832 (\:.l\ dated 1833). 



C. Davies Sherborn 

 (' Index animaliura '). 



