THEIR ALLIES. 83 
‘besides those entombed in its crust, as fossils, which can 
never be numbered. 
Thus the idea of articulation, upon which Cuvier found- 
ed this branch of the animal kingdom, which begins so 
simply in the worm and grows far more complex in the 
crab and its allies, is,in the insect, carried out with a 
bewildering richness and profusion of detail. It is like 
comparing a savage’s “dug out” to the “Great Eastern” 
steamship, or the rude wigwam of an Indian to the 
Cathedral of Milan. 
The German Naturalist Oken, who in his writings has 
. so often anticipated the results of subsequent laborious 
inquiries, said in his aphoristic style when discoursing of 
insects: “Every fly creeps as a worm out of the egg; 
then by changing into the pupa, it becomes a crab, and, 
lastly, a perfect fly.” The motions of these worms and 
crabs to which he aptly compares the two stages of the 
young fly, will show a farther analogy, though to many it 
may seem fanciful, between these forms of jointed animals. 
Worms wriggle along as they move. Now wriggling is 
one of the lowest forms of locomotion. The waddling of 
geese partakes of the same nature. In worms,,the many 
rings of the body, so similar to each other in form and 
size, move on themselves, and then move all together, 
and thus the creature progresses. In pepe the abdbiheti 
moves upon the forward part of the body; the insect 
jerks about by the motive power residing in the abdomen. 
Here is indeed a localization of the power of motion, and 
something is gained in the rising scale. Now the Crus- 
tacea, or crabs and their allies, all move by jerking. 
Watch the microscopie Cypris or larger Cyclops, i in its 
swift circumnavigation of a drop of water. It moves 
both by its thoracic legs, and by the Isomat 
