700 The American Naturalist. [August, 
colors of their neighbors, in another, the least obtrusive mim- 
icry will be exemplified. The stranger has often to examine 
carefully before, in the seemingly empty tank, he can deter- 
mine on every side the living forms whose color characters 
screen them effectively. Thus he will see sand-colored rays 
and flounders, the upturned eyes of the curious star-gazer 
almost buried in the sand, a series of mottled crustaceans 
wedged in a rocky background, an occasional crab wandering 
cautiously about, carrying a protective garden of seaweeds on 
his broad back ; odd sea horses posing motionless, mimicing 
the rough stems of the seaweeds. In the larger tank sea tur- 
tles float sluggishly about; and coiled amid broken earthern 
jars, are the sharp-jawed murrys, suggestive of Roman din- 
ners and of the cultural experiments of Pollio. Aération in 
the aquaria is secured effectively by streams of air which are 
forced in at the water surface and subdivide into bright 
clouds of minute silvery bubbles. The tanks are cared for 
from the rear passage-ways; attendants are never seen by 
visitors and constant attention has given the aquaria a well 
earned reputation. Descriptive catalogues with figures 
enable the stranger to better appreciate the aquarium. 
To the remainder of the building strangers are not admit- 
ted. A marble stairway leads from the door of the aquarium 
to a loggia which opens into the territory of the students. A 
long pathway of grating extends across the open center of 
the building,—whose skylight top admits the light to the aqua- 
rium below. On the one hand is the main laboratory room, 
on the other the library and separate rooms intended for more 
fortunate investigators. One enters the main laboratory, 
passes a wall of student aquaria and sees a series of alcoves 
formed by low partitions, each work place with its occupant, his 
apparatus, his books, his jars,—altogether often a picture not 
of the utmost tidiness. A small iron staircase leads to a gal- 
lery which gives a second tier of work places and doubles the 
working capacity of the room. Here, side by side, will be 
representative workers from universities of every country of 
Zurope. 
The library room adds not a little to the attractiveness of 
the Naples station. It is a long room, and, as shown in 
