118 PEACH. ROOT^SOW-BUGS- 



the animals under consideration pertain to the order Isopoda, Le^ 

 equal-footed, having fourteen pairs of legs of nearly equal size, 

 and to the family Onisgid^:, which, like other families of this 

 order has four antennae, but here the inner pair of these antennae 

 is quite short and, little apparent, consisting at most of only two- 

 Joints. The typical genus of this family, named Oni&cus by Lin- 

 naeus, is by modern naturalists restricted to those species in which 

 the external antennae have eight juints, the three la^-.t joints being 

 much more slender than the others, and the sutures separating 

 them much less distinct than those between the other joints. I 

 have never met with any Americas species having this number of 

 j&ints to the antennae. The genera Porcellio and Armadillo differ 

 from Oniscus in having the slender terminal portion of the an- 

 tennae divided into but two joints instead of three, making th© 

 nnbiber of joints seven in all. 



The genus Armadillo is distinguished from Porcellio, and from 

 Oniscus also, by being destitute of the two conical projectiiig 

 points or short tail-like processes which we observe at the tip of 

 the abdomen in those genera, and also by having the faculty of 

 rolling itself into a ball, resembling when thus rolled up a pea or 

 pill, whence they are popularly named pill-millipedes. We have 

 one or more species of these inhabiting the southern part of the 

 State and Long Island, but they do not extend to the neighbor- 

 hood of my residence, and I have not examined them sufficiently 

 to determine whether they are different from the European species 

 of this genus. , 



,A11 the animals of this family which have yet been discovered 

 in the central and northern sections of our State pertain to the 

 genus Porcellio. These crustaceans are everywhere common 

 ahout the roots of trees, under logs and stones, in the crevices of 

 the foundation walls of our buildings and in our cellars, and they 

 are particularly numerous under any logs or billets of wood 

 which are kft in our chip yards. They occur, in short, in all 

 situations that are damp, cool and dark. Frequently, by night 

 in wet weather, they crawl about the rooms in our dwellings. 

 They are perfectly innocent and harmless, subsisting upon decay- 



