CARBONirEROUS AGE. I3 



because a living species of that group was found at the Cape of Good Hope I Or, 

 if a naturalist should dredge up from the bottom of some unexplored sea, a living 

 Ammonite, Avould Palaeontologists admit his right to change the name of the genus "? 

 The other instance where we have restored an older name, is in adoptino- 

 EljpUdium, Montfort, instead of Polystomella, Lamarck, Montfort's name having 

 been published in 1808, in his Conchyl. Syst., Vol. I, pp. 14-15. It is true, nol 

 very much can be said for his figure or description, but as he refers to the figures 

 and description of Von Fitchell and Von Moll, so that later authorities do not 

 hesitate to identify the type of his genus with a species of Polystomella, Lamarck, 

 which name was not published until 1822, we feel bound to adopt his name. The 

 fact that he gave some five or six other generic names to other species and varieties 

 of the same genus on subsequent pages of his work, does not alter the case, for it 

 matters not how many names an author may give a genus, we are bound to adopt 

 his first name, if not pre-occupied, and his type can be identified, and does not 

 belong to a previously described genus ; the subsequent names of course falling 

 into the List of synonyms. 



I 

 Genus FUSULINA, Fischer. 



Synon.—FusuUna, Fischer, Oryot. du Gouv. de Mosoou, 1837, p. 12G.— D'Okbignt, in Murchison, Verneuil & Keyser- 

 ling's Geol. Euss. II (part iii, Pal.), 1845, p. 15.— Cone., Element, de Geol. Strat., II, 1852, 169. 

 Borelis (sp.), Ehkeneekg, Berlin Monatsb. 1842, 274 (not Montfort, 1808). 

 Etym. — Fusus, a spindle. 

 Type. — Fusulina cylindrica, Fischer. 



Shell regular, equilateral; fusiform, cylindrical or subglobose, according to its 

 greater or less elongation in the direction of the axis, sometimes constricted 

 around the middle; symmetrically involute so that each turn envelops aU the 

 preceding at all stages of growth. Surface with nearly parallel, subequidistant 

 furrows coincident with the septa within, and running in the direction of the 

 axis. Aperture a narrow slit confined to the central region. Foramina passing 

 through the external walls of the chambers, of moderate size. Septa compara- 

 tively narrow in the middle, and gradually widening towards the extremities; 

 apparently composed each of a single lamina; regidarly undulated laterally, so as to 

 partly subdivide each intervening chamber on each side of the broad mesial avenue 

 (connecting the different chambers) into a series of small alternately arranged cells 

 'connected together by narrow galleries. Internal canal system, and " intermediate 

 skeleton" apparently wanting. 



The shells of this genus present the various modifications of form, and much the 

 general appearance of the genus Alveolina, from which, however, they can be 

 readily distinguished by their aperture consisting of a single mesial slit, instead of 

 a single or multiple series of round or oval openings extending along the entire 

 length of the shell. They also diff"er entirely in their internal structure, the differ- 

 ent chambers in Fusulina being connected with each other by the single broad 

 mesial slit corresponding to the aperture ia the last or outer septum, and not sub- 



