^C. sitchensis.^ The most striking characteristic of this singular species is the great development of the carapace, which forms a broad, thin shield extending beyond the body and legs, and completely hiding the animal beneath it. The carapace is smooth and uneven, has a high ridge through the center of the anterior part, and the sides are broadly expanded and bluntly pointed at the extremity. The rostrum appears like a small rectangular piece cut out of the anterior side of the carapace. This species is found in the Strait of Fuca. A similar species, /C. typicus/, is found near low-water mark on the surf-washed rocks of the beach at Monterey, California. (Plate LXII.) GENUS ^Phyllolithodes^ ^P. papillosus.^ The carapace is triangular, about two inches wide at the base, and narrowing to a long, pointed rostrum which terminates in a forked spine. The surface of the carapace is deeply depressed in parts, and forms a heart-shaped figure in the center. The lateral margins have four prominent spines on each side, the two at the posterior ends being [pg272] thicker than the other two. The abdomen is broad, covering the whole under side of the body, and is marked off with prominent raised ridges diverging from the center line. The legs are all beset with long, rough spines. Habitat, the northwest coast. Taken from the stomachs of fishes off Monterey, California. (Plate LXII.) SUBORDER ~BRACHYURA~ THE CRABS This group contains the true crabs, which are the highest of the /Crustacea/. In form they are quite the reverse of the first group. In the /Macrura/—except in the anomalous forms—the body is long and cylindrical and the abdomen extended, but in the /Brachyura/ the body is flat and broad and the abdomen short and reflexed. Crabs of this suborder inhabit all seas of the globe, and are found from the shore to great depths. Some species live on land, some on the shore, some in deep water. Some forms burrow in the sand; others live under stones and boulders, or conceal themselves in crevices of rocks or in the cavities of sponges. They are divided into many families, and creep, climb, swim, or burrow, their structure being modified to their respective modes of life. There is also great variation in their shapes as well as in their color and markings. This diversity is so great and peculiar that it seems as though each one were more curious than the others.