MARINE INVERTEBRATA OF GRAND MAN AN. 53. 



taken. It occurred only once, but then in considerable numbers, in ten fathoms, 

 on a sandy bottom, inside of Duck Island ledge. It resembles Acantlwsoma Tiystrix, 

 Owen, which, however, has no rostrum. Certain northern Acanthonoti also ap- 

 proach it in external appearance; but the characters of the legs of the first two 

 pairs separate it from that genus. In its very hard carapax and large strong 

 epimera, it possesses great security ; and, when disturbed, it rolls itself up and 

 remains quiescent, as if feigning death, as is the manner of some spiders. Most 

 other Amphipods will, on the contrary, endeavor to escape when molested. When 

 in motion, this animal preserves an erect posture, like the Isopods, with its tail 

 bent up underneath. It seldom swims, but makes powerful leaps by means of its 

 well-developed caudal stylets. 



Amphithoe^ virescens, St., n. s. Slender, of a softer structure than is usual, 

 smooth and rounded above. Epimera small, rounded below. Head of moderate 

 size, with very small red eyes.^ Antennae about equal in length, more than half 

 as long as the body ; the superior ones with flagella constituting nearly two-thirds 

 of their length ; the inferior ones thick-based, and slightly subpediform. Mandibles 

 large, with their curved apices long and projecting. Legs covered with long 

 simple hairs ; the first two pairs with hands of moderate size, equal ; posterior three 

 pairs with strong, hooked, terminal articles. Caudal stylets of the first two pairs 

 spinous above ; those of the last pair with short, thick rami, the outer ones having 

 two hooks at their extremities above, the inner ones simply hairj'. Natatory feet 

 of great length. Color, pale-greenish, with minute black punctge distantly and 

 regularly arranged, most numerous on the epimera. Length, 0.45 inch ; height at 

 the fourth segment, 0.1 inch ; breadth, 0.08 inch. Dredged in four fathoms, on a 

 nullipore bottom, off Duck Island boat-moorings. 



A. MACULATA, St., n. s. Body rather broad, smooth and well rounded above ; 

 epimera of moderate size, those of the fifth pair largest ; antennae rather stout, sub- 

 equal ; inferior ones subpediform, with very short terminal articles ; hands of the 

 second pair of legs larger than those of the first pair ; posterior five pairs with 

 small, sharp, curved nails ; fifth pair very short ; caudal stylets short and thick. 

 Color greenish or grayish, with very numerous minute punctations, and a white 

 spot on each of the segments along the middle of the back. Length, 0.65 inch ; 

 breadth, 0.14 inch; height at the fourth segment, 0.15 inch; length of antennae, 

 0.22 inch ; of the second pair of legs, 0.2 inch ; of the head and first five segments 

 together, 0.34 inch ; of the abdomen, 0.28 inch. Taken on rocky bottoms in the 

 laminarian zone, and occasionally at low water. It difiers from the last species in 

 being more robust and of a much harder structure ; also totally in coloration. 



Iphimedia vulgaris, St., n. s. Smooth, subcompressed, abdomen with segments 

 slightly projecting at the articulations, but not dentated ; head large, with very 

 large reniform eyes, which are colorless in preserved specimens. Antennas sub- 



' The genus is here taken as restricted by Dana ; to those species which have large epimera of the fifth 

 pair, and uncinate external rami to the posterior caudal stylets. 



^ The color of the eyes is quite characteristic of the species in the Amphipoda. It is, however, only to 

 be observed in living individuals; as the eyes invariably become either black or colorless after death. 



