eotalina ; calcarina; fusulina. 505 



to a Spur- rowel (Plate xvi., fig. 3). The solid club-shaped 

 appendages with which this shell is provided, entirely belong 

 to the ' Intermediate Skeleton ' b, which is quite independent 

 of the chambered structure a ; and this is nourished by a 

 set of Canals containing prolongations of the Sarcode-body, 

 which not only furrow the surface of these appendages, but 

 are seen to traverse their interior when this is laid open by 

 section, as shown at c. In no other recent Foraminifer does the 

 Canal-system attain a like development ; and its distribution in 

 this minute Shell, which has been made out by careful micro- 

 scopic study, affords a valuable clue to its meaning in the com- 

 paratively gigantic Fossil organism to be presently described under 

 the designation Eozoon Canadense (§ 397). 'The resemblance which 

 Calcarina bears to the radiate forms of Tinoporus (Fig. 254) which 

 are often found with them in the same Dredgings, is frequently 

 extremely striking ; and in their early growth the two can scarcely 

 be distinguished, since both commence in a Rotaline spire with 

 radiating appendages ; but whilst the successive chambers of 

 Calcarina continue to be added on the same plan, those of Tino- 

 porus are heaped-up in less regular piles. 



388. Certain beds of Carboniferous Limestone in Russia are 

 entirely made-up, like the more modern Nummulitic Limestone 

 (§ 392), of an aggregation of the remains of a peculiar type of 

 Foraminifera, to which the name Fusulina (indicative of its fusi- 

 form or spindle shape) has been given. In general aspect and 

 plan of growth it so much resembles Alveolina, that its relation- 

 ship to that type would scarcely be questioned by the superficial 

 observer. But when its mouth is examined, it is found to consist" 

 of a single slit in the middle of the lip ; and the interior, instead 

 of being minutely divided into chamberlets, is found to consist of 

 a regular series of simple chambers ; while from each of these 

 proceeds a pair of elongated extensions, which correspond to the 

 'alar prolongations' of other spirally-growing Foraminifera (§ 391), 

 but which, instead of wrapping round the preceding whorls, are 

 prolonged in the direction of the axis of the spire, those of each 

 whorl projecting beyond those of the preceding, so that the shell 

 is elongated with every increase in its diameter. Thus it appears 

 that in general plan of growth Fusulina bears much the same 

 relation to a symmetrical Rotaline or Nummuline shell, that Alveo- 

 Una bears to Orbiculina; and this view of its affinities is fully 

 confirmed by the Author's microscopic examination of the struc- 

 ture of its shell. For although the Fusulina-limestone of Russia 

 has undergone a degree of metamorphism, which so far obscures 

 this character that he could not speak confidently of the shells of 

 which it is composed, yet the appearances he could distinguish 

 were decidedly in its favour. And having since received speci- 

 mens from the Upper Coal Measures of Iowa, U. S. , which are in 

 a much more perfect state of preservation, he is able to state with 



