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thej have a depth often as great as 3^ lines. Their height 

 varies from 3^ to 9^ lines. The tallest are the oldest, and have 

 continued growing with their younger neiglibors. The greater 

 diameter is from 4 to 6 lines, and the difference between the 

 longitudinal and transverse diameters is occasionally as great as 

 6 to 3^ ; at other times the calicles are nearly round. In the 

 longitudinal axis there usually lie two lamella? of the first cycle, 

 which shows a tendency to a bilateral symmetry. The larger 

 calicles have from 48 to 74 lamella% so that there are four cycles, 

 and sometimes part of a fifth. Those of the last cycle, however, 

 are very small and thin, and can scarcely be seen without a lens. 

 The six that make the first cycle are conspicuous for their size ; 

 they are rounded at their upper ends, exsert, often as much as a 

 line, and are thicker than the wall of the calicle. Their sides 

 are covered with grains, arranged more or less regularly in 

 curved lines, running from the wall to the edge of the lamella. 

 Wherever one of these lines ends on the margin, it projects a 

 little, and thus the edge of tlie lamella is toothed. The lamellae 

 of the second and third cycles do not materially differ, except in 

 size, from those of the first. The lamella? are not confined within 

 the limits of the wall of the calicle, but appear on its outside, as 

 vertical ridges or striaa, extending often from top to bottom ; in 

 some instances, however, they are nearly covei-ed by marine in- 

 crustation to within a line of the top ; and, again, they may be 

 obliterated by the growth outwards of the wall. These ridges, 

 which may properly be called the outer edges of the lamellae, are 

 thicker than the inner edges, but present, to a greater or less 

 degree, the same granular teeth. The smallest lamella? occa- 

 sionally bend sidewise and join their neighbors, a feature observed 

 in its perfection among the Eupsammidte, and, to some extent, in 

 other families. The columella is frequently wanting, or repre- 

 sented only by one or two lamellar teeth ; but, on the other hand, 

 it may form, at the bottom of the calicle, a spongy mass, two or 

 three lines in diameter. The wall, at its upper margin, is very 

 thin and diaphanous ; outside, in the spaces between the lamellfe, 

 it is slightly granulated. It is highly probable that the polyp, 

 like the Garyophyllia solitaria, has the protruded, Caryophyllian 

 mouth, and about twenty-two short tentacles, in two rows ; and 

 farther, that it has the power of raising itself above the edge 



