GENUS ALVEOLINA. 99 



found in the Tertiarics of St. Domingo ; and the type is also found fossil in a white 

 (Tertiary ?) limestone at Corfu. 



Gejius IX.— Alveolina (Plate VIII, figs. 13—15). 



146. Histori/. — Most of the examples of this type at present known are fossils, occurring 

 in association with Nuutiutilites, Orhltolites, &c. in the Nummulitic limestone, or in other 

 formations which represent it ; and those first described (by Fortis) were confounded with 

 Nummulites and Orbitolites under the term Discolithus. By Fichtel and Moll (xlv) they were 

 ranked as a sub- type of their comprehensive genus Nautilus. The designation Alveolites was 

 first given to this type by Bosc,* who erroneously referred two minute forms of it to a genus 

 which had been previously established by Lamarck (lvii) for a group of corals ; but Montfort, 

 (lxvii), not accepting this determination, raised three of Bosc's species to the rank of genera, 

 under the names of Borelis, Clausulus, and Miliolites. Lamarck did not adopt either Bosc's 

 or Montfort's generic designations, but substituted new ones (lix, lx), Melonites for the fossil, 

 and Melonia for the recent forms. Defrance (xxix) proposed yet another. name, Ori-aria. 

 And finally M. D'Orbigny (lxix) adopted Bosc's name, with a slight alteration in its termi- 

 nation, which served at the same time to mark the continued existence of the type, and to 

 distinguish it from the Lamarckian genus of Corals. The name Alveolina was soon afterwards 

 adopted by M. Deshayes (xxx), and it may now be considered as the established designation 

 of the genus, the synonymy of which has recently been very fully treated by Messrs. 

 W. K. Parker and Rupert Jones (Lxxxa). 



147. External Characters.- — The recent specimens upon which my investigations have 

 been made belong to a fusiform variety which was tolerably abundant both in Mr. Jukes's 

 Australian dredgings, and in Mr. Cuming's Philippine collection ; they were obviously identical 

 specifically, but those from the latter source considerably exceeded those from the former in 

 average size. The length of the longest complete specimen in my possession is '35 of an 

 inch ; but I have a specimen whose shape is nearly cylindrical (the A. Quoii of D'Orbigny), 

 which, though incomplete at one end, measures "50 of an inch. The ordinary form, from 

 which any considerable departure is very rare, is that which is exhibited in Plate VIII, fig. 13; 

 and it is obviously produced, as correctly stated by M. D'Orbigny, by the involution of a 

 spiral around an elongated axis. The surface is marked out by depressed septal bands into 

 a succession of segments of tolerably uniform breadth ; and each of these segments is crossed 

 by secondary furrows, which lie so closely together as to mark out each into a series of very 

 elongated areolae, that remind us of the oblong superficial areolae of the complex type of 

 Orbitolites (Plate IX, fig. 7), but are much narrower in proportion to their length. The 

 apertural plane of the spire is closed by a solid wall, the surface of which is nearly flat, and 



* 'Bulletin des Seances de la Societe Philomathique,' No. CI. 



