22 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [316] 
it loves to dwell. It is found nearly up to high-water mark, and has a 
wide range both northward and southward along the coast. 
Another very common and much larger isopod is the Idotea irro- 
rata, (Plate V, fig. 23,) which grows to be nearly an inch long. Its 
colors are extremely varied. Often the general color is dark gray, light 
gray, dull green, or brownish, thickly specked and blotched with darker, 
but the colors are often brighter and the markings more definite; not 
unfrequently a band of white, or yellowish, or greenish, runs along the 
middle of the back, with perhaps another along each lateral border. 
This species occurs creeping among the “ rock-weeds” and other alge 
at low water, in the pools, creeping on the under sides of stones, ad- 
hering to eel-grass, and also among floating sea-weeds, away from the 
shore, and in many other situations. Its colors are generally well 
adapted for its concealment, by imitating, more or less perfectly, the 
rocks and weeds among which it lives. Even those with bright green 
markings are thus protected when living on eel-grass or Ulva ; the dark, 
obscurely marked ones when on dead eel-grass or dark Fucus ; the grays 
and browns when on stones and among barnacles, &c. This protection 
is not perfect, however, for they often fall victims to hungry fishes of 
many kinds. 
The Idotea phosphorea HARGER, is a closely allied species, which 
grows even larger. It can easily be distinguished by the tail-piece, 
which is acute in this, but tridentate in the last, and by its rougher sur- 
face and more incised lateral borders. Its colors are similar and equally 
variable, though they are frequently in larger and more definite spots 
and blotches, and the light spots are often bright yellow. It is, as its 
name indicates, decidedly phosphorescent. It lives under the same cir- 
cumstances as the preceding species, but is much less common in this 
region, though it is abundant in the Bay of Fundy. It often occurs 
among the crowded stems of Corallina officinalis in the larger tide-pools. 
Another related species, the Hrichsonia filiformis HARGER, (Plate 
VI, fig. 26,) also occurs among the Corallina and other alge in the tide- 
pools. This is a smaller species than the two preceding, but is some- 
what similar in its colors, which are equally variable and equally adapted 
for its concealment; in this the colors are more commonly various tints 
of brown, or dull reddish, or light red, which are well adapted to blend 
with the colors of the Corallines. Quite a different looking creature is the 
Epelys montosus, which is occasionally found concealed beneath stones 
where there is more or less mud. This species also frequents muddy 
bottoms, and is pretty effectually concealed by its rough-looking back 
and the coating of mud and dirt that always adheres to it. 
Clinging to the hydroids and delicate alge on the under sides of 
stones, and in tide-pools, curious slender-bodied crustacea belonging to 
the genus Caprella (similar to fig. 20, Plate V) may often be found in 
considerable numbers, but they are still more abundant on rocky bot- 
toms off shore. They have the habit of holding on firmly by the pos- 
