OF THE ANNULOSA. 393 



logy be pursued, we also perceive why Pallas was induced 

 to give the trivial name of Scolopendroides to a species of 

 Caprella, — why the Amphipoda have been characterized by 

 the setaceous appendages of their abdomen, — why these 

 Crustacea leap, — why the genus Thalassina imitates the 

 form of a Scorpion, — why naturalists, conversant with 

 this branch of Natural History, have, since the days of 

 Aristotle, all compared the genus Pagurus to Spiders, — 

 why some species of the genus Epeira resemble Decapod 

 Crustacea so much as from them to have borrowed their 

 name. These, and a thousand similar cases, are all rela- 

 tions of analogy, which may be explained by the bare in- 

 spection of the above columns. 



But it will be said that the Arachnida and Haustellata 

 are according to the table of affinity contiguous circles, and 

 yet the corresponding points in the columns do not coincide 

 analogically. This struck me at first, I confess, as some- 

 thing unaccountable; but a very little attention to the sub- 

 ject served to show that it could not be otherwise, as these 

 columns only represent half the course of the analogies 

 which appear on the inspection of the preceding table of 

 affinities. By a reference to that table^the entomologist will 

 perceive that the; corresponding points of these contiguous 

 circles have an analogy, which, I doubt not, would be even 

 more conspicuous if the groups of Arachnida were only 

 more accurately defined. Even assuming their accuracy as 

 they have been described in the foregoing pages, surely we 

 may consider the faculty of spinning, which is common 

 both to Spiders and Lepidopterous larva?, to be one of 

 analogy. Surely the iSepa or lianatra, with its cheliform 

 anterior feet, its caudal appendage, its habit of carrying its 

 progeny on its back, deserves the title of Water Scorpion, 

 which it has acquired in almost every European language. 



