BREAKFAST-TABLE ZOOLOGY 13 
enable a man to discern, from a comparison of the lobster 
alone with its entomostracan parasite, that they are alike 
crustaceans, which is, nevertheless, known to be the case. 
In a dishful of prawns it may often be noticed that one or 
two of the finest have the head swollen on one side, as if 
the creature were suffering from a face-ache. There is no 
special reason to suppose that the prawn thus affected is 
suffering any great inconvenience. Itis merely lending the 
shelter of its carapace to a family of isopod crustaceans. 
Comfortably ensconced in the bulging cheek-piece will be 
found a misshapen animal of no inconsiderable size, in 
general laden with innumerable eggs, and accompanied by 
a far smaller partner, the father of the brood, symmetrical 
in form, and retaining some of the freedom of movement 
which belongs to the young when first hatched, but which 
the mother has entirely resigned. Thus the zoology of 
the breakfast table will supply examples of three very dis- 
tinct orders. These examples are none the less curious 
because they happen to be common. Any one who is 
content to examine them with care will thereby lay a 
simple and solid foundation for all subsequent study in 
the realm of carcinology. 
The novice, however, need not be dependent on the 
fishmonger for specimens. In cellars, gardens, hedges 
and ditches, under flat stones, in dry moss, among moist 
dead leaves, in the Joosened decaying bark of trees, crusta- 
ceans are to be met with almost everywhere. These are 
the so-called wood-lice, including those known by the 
trivial names of Pill-bugs and Slaters, Millepedes, and 
Carpenters. One species, small and white and slow in 
movement, is frequently to be found in ants’ nests, and 
seemingly never elsewhere. All this set of animals, 
though air-breathing and living on land and often possess- 
ing great agility, belong to the Isopoda in common with 
the marine species above mentioned that leads its apathetic 
life within the carapace of the prawn. 
From almost every little brook and pond in England 
the amphipod, Gammarus pulez, and the isopod, Asellus 
aquaticus, may be fished without difficulty and without 
