172 A WONDERFUL ARRANGEMENT. 



oviparous or viviparous ? I defy you to show me anywhere a 

 single wood-louse's egg. Have the patience to observe our 

 crustaceans more nearly. Among the crowd, you will remark 

 some they are the females with a kind of membraneous 

 pouch underneath the body, stretching from the head to the 

 fifth pair of legs. The pellicle which forms this pouch is so 

 thin, and so transparent, that you can distinguish the eggs 

 within it. These eggs, instead of being expelled for incuba- 

 tion, remain in the mother's pouch until they are hatched. At 

 that felicitous moment, the membranous bag splits cross-wise, 

 longitudinally and trans versally, to permit the emergence of 

 the young wood-lice. The latter are extremely small, and in 

 form resemble nothing in the world so much as a little white 

 line (Fig. 35, b). They differ from their parents only in having 

 one pair of feet, and one ring less than they have. They 

 undergo no metamorphoses. After their birth, the little ones, 

 which have proportionally very large antennae, do not imme- 

 diately separate from their mother. By a wonderful act of fore- 

 thought on the part of Nature,* they keep themselves con- 

 cealed in the middle of the respiratory lamina, which garnish 

 the under part of the tail 



The specific characters of the Oniscus asellus are tolerably 

 well defined. By its rings of dark gray, a little lighter at the 

 edges, which form for it an articulated, glossy carapace, marked 

 with white spots, longitudinally arranged ; by the uniform pale 

 gray colour of its belly and its legs, covered with scattered 



* That is, the Creative Power which, in common parlance, we choose to 

 call Nature. 



