. Bulletin - United States National Museum. Science. 212 BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM have two or three grooves and ridges, but the sixth abdominal somite has otherwise no special ornamentation or sculpture. (2) The cara- pace is produced into an acute triangular rostral plate with a bluntly rounded apex. (3) The antennal scale is seven times as long as broad. (4) The endopod of the third to the eighth thoracic limbs has the sixth joint divided into four to six subjoints. (5) The inner uropod has a row of five spines on the lower margin near the statocyst, (6) The telson (fig.
. Bulletin - United States National Museum. Science. 212 BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM have two or three grooves and ridges, but the sixth abdominal somite has otherwise no special ornamentation or sculpture. (2) The cara- pace is produced into an acute triangular rostral plate with a bluntly rounded apex. (3) The antennal scale is seven times as long as broad. (4) The endopod of the third to the eighth thoracic limbs has the sixth joint divided into four to six subjoints. (5) The inner uropod has a row of five spines on the lower margin near the statocyst, (6) The telson (fig. 88) is narrowly triangular in shape, two and a half times as long as broad at the base, apex narrowly truncate, almost rounded, and armed by two pairs of spines, the outer pair twice as long as the inner pair and considerably stouter; the lateral margins are armed with about 27 large spines extending throughout the entire length of the margin and increasing very conspicuously in length toward the apex; on the distal three-quarters of the margins there are small spines between the large ones; proximally only two or three small spines between the large ones, but the number gradually increases so that dis- tally there may be 10 to 12 small spines between the larger ones. The present material is defective and much damaged but appears to agree very closely with Dershavin's description. The telson has many more small spines between the larger spines on the lateral margins, especially distally, than would appear from the figure given by Dershavin. Since no details are given in the description it is a little difficult to decide how much im- portance should be given to this point. In other characters, antennal scale, rostral plate, inner uropods, and the folds on the abdominal somites, these specimens agree very closely with A. stelleri, and provisionally at any rate I refer them to this species. The material is so badly damaged that the drawing of the telson here given had to be made f
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Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
