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THE POPULAR SCIENCE MONTHLY. 



or Lingulella (Fig. 3, ), another genus of these animals, has persisted 

 from the Cambrian age (A, c) to our own times, presenting little or no 

 change for the attention of the geological chronicler. The curious 

 king-crabs, or LimuU (Fig. 4), of the West Indies are likewise pre- 



FlG. 3. LiNGULA. 



Fig. 4. King Crab. 



sented to our view, with little or no variation, from very early ages of 

 cosmical history ; and of the pearly nautilus (Fig. 8) now remaining 

 as the only existing four-gilled and externally shelled cuttle-fish the 

 same remark holds good. The fishes, likewise, are not without their 

 parallel instances of lack of change and alteration throughout long 

 ages of time. The well-known case of the genus Beryx presents us 



w4th a fish of high organi- 

 zation, found living in the 

 Atlantic and Pacific Oceans, 

 and which possesses fossil 

 representatives and fac - 

 similes in the chalk (Fig. 

 5.) From the latter period 

 to the present day, the 

 genus Beryx has therefore 

 undergone little modifica- 

 tion or change. The same 

 remark certainly holds good of many of those huge " dragons of the 

 prime " (Figs. G and 7), which reveled in the seas of the Trias, Oolite, 

 and Chalk epochs developed in immense numbers in these eras of 

 earth's history, but disappearing for ever from the lists of living 



Fio. 5. Bektx. 



