[369] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. (i 
by such fishes as are able to capture it. When living the colors are 
quite elegant. Along the back there is a broad band of mottled, red- 
dish brown, which is contracted on the next to the last segment; each 
side of this band the mottlings are fewer, and the surface somewhat 
hairy. The last segment and the appendages of the preceding one are 
thickly specked with reddish brown; their edges are fringed with gray 
hairs. The Calianassa Stimpsoni Smitu, (Plate I, fig. 8, large claw,) is 
also a burrowing species, but its habits are at present little known, owing 
to its rarity. It has been found in the stomach of fishes, and is proba- 
bly more common farther south. 
The Squilla empusa is a very interesting creature, whose habits are 
still imperfectly known. It is often thrown on the beaches by the 
waves, and probably it usually burrows in the mud below low-water 
mark, but in certain localities it has been found burrowing at or near 
low-water mark of spring-tides, forming large, irregular holes. The very 
curious, free-swimming young (Plate VII, fig. 36) were often taken in 
the towing-nets. Large specimens are eight orten inches long and about 
two broad. The body is not so stout built as that of the lobster, and the 
carapax or shell is much smaller and softer, while the abdomen is much 
larger and longer in proportion. The legs and all the other organs are 
quite unlike those of the lobster, and the last joint of the great claw, in- 
stead of forming a pair of pincers with the next, is armed with a row 
of six sharp, curved spines, which shut into corresponding sockets, 
arranged in a groove in the next joint, which also bears smaller spines. 
By means of this singular organ they can hold their prey securely, and 
can give a severe wound to the human hand, if handled incautiously. It 
also uses the stout caudal appendages, which are armed with spines, very 
effectively. The colors of this species are quite vivid, considering its 
mud-dwelling habits. The body is usually pale green or yellowish green, 
each segment bordered posteriorly with darker green and edged with 
bright yellow; the tail is tinged with rose and mottled with yellow and 
blackish ; the outer caudal lamelle have the base and spines white, the 
last joint yellow, margined with black; the inner ones are black, pale 
at base; the eyes are bright emerald-green; the inner antennie are 
dark, with a yellow band at the base of each joint; and the flagellum 
is annulated with black and white. 
The common shrimp, Crangon vulgaris, (p. 339, Plate III, fig. 10,) is 
frequent on muddy shores, where it has a darker color than when liy- 
ing on sandy shores. The common prawn, Palemonetes vulgaris, (p. 339, 
Plate ITI, fig. 9,) is also common in such situations, especially where 
there is eel-grass, among which it finds its favorite resorts, but it is 
still more abundant in the estuaries. Another shrimp, the Virbius <zos- 
tericola Smuru, also occurs among the eel-grass, in similar places. It is 
usually greenish in color. 
Two other species of shrimp-like crustacea, belonging to the genus 
Mysis, are also found on muddy shores, especially among eel-grass. 
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