6 
The analogies existing between the limulus 
and our fossil, as we mentioned in another 
place, have been shown by Dr. Dekay and 
others. 
In further illustration of this subject, we 
here add, with some slight alterations, from 
Dr. Buckland’s admirable Bridgewater trea¬ 
tise, a considerable part of his section on the 
trilobites, which exhibits in a very condensed 
form the facts and opinions which have any 
bearing on this enquiry. I have greater satis¬ 
faction and more confidence in referring to 
his remarks, than in attempting to offer any 
thing of a similar nature drawn up by myself. 
After mentioning that the serolis is the 
nearest approach among living animals to the 
external form of trilobites, he adds, the next 
“ approximation to the character of trilobites 
occurs in the limulus or king crab, a genus 
now most abundant in the seas of warm cli¬ 
mates, chiefly in those of India, and of the 
coasts of America. The history of this genus 
is important, on account of its relation both 
to the existing and extinct forms of crusta- 
