290 NUMMULITE. 



s The Nummulites, like the Nautilus and Ammonite, are 

 divided into air-chambers, which served the office of a 

 iioat : but there is no enlargement of the last chamber which 

 could have contained any part of the body of the animal. 

 The chambers are very numerous, and minutely divided by 

 transverse plates ; but are without a siphuncle.* The form 

 of the essential parts varies in each species of this genus, 

 but their principles of construction, and manner of operation, 

 appear in all to have been the same. 



The remains of the Nummulites are not only animal 

 bodies which have contributed to form the calcareous strata 

 of the crust of the earth ; other, and more minute species of 

 Chambered shells have also produced great, and most sur- 

 prising effects. liamarck (Note, v. 7. p. 611,) speaking of 

 the Miliola, a small moltilocular shell, no larger than a mil- 

 let seed, with which the strata of many quarries in the neigh- 

 bourhood of Paris are largely interspersed, notices the im- 

 portant influence which these minute bodies have exercised 

 by reason of their numerical abundance. We scarcely con- 



Clio Borealis, that in calm weather, the surface of the water in these seas 

 swarms with such millions of these mollusks (rising for a moment to the air 

 at the surface, and again instantly sinking towards the bottom,) that the 

 whales can scarce open their enormous moutlis without gulping in thou- 

 sands of these little gelatinous creatures, an inch long, which, together with 

 Meduss, and some smaller animals, constitute the chief articles of their food ; 

 and we have a farther analogy in the fact mentioned in Jameson's Journal, 

 vol. ii. p. 12. " That the number of small Medusse in some parts of the 

 Greenland seas is so great, that in a cubic inch, taken up at random, tliere 

 are no less than 64, In a cubic foot this will amount to 110,592; and 

 in a cubic mile (and there can be no doubt of the water being charged with 

 them to that extent,) the number is such, that allowing one person to count 

 a million in a week, it would have required 80,000 persons, from the crea- 

 tion of the world, to complete the enumeration." — See Dr. Kidd's admirable 

 Introductory Lecture to a course of Comparative Anatomy, Oxford, 1824^ 

 p. 35. 



* In PI. 44, Figs. 6, 7, sections of two species of Nummulite are copied 

 from Parkinson. These show the manner in which the whorls are coiled 

 up round each other, and divided by oblique septa. 



