OCR Text |
Show 58 MR. E.J. MIERS ON CRUSTACEA FROM [Jan. 14, HETEROCUMA SARSI, sp. n. (Plate III. fig. 3.) The body is slender ; the carapace or dorsal shield is somewhat laterally compressed, with an obscure median dorsal keel, which is flattened and sulcated posteriorly, and terminates anteriorly in the oculigerous lobe. Viewed laterally, the dorsal outline of the carapace is nearly straight, the inferior or lateral margin is at first straight and parallel with the upper, but anteriorly it is curved upward toward the front. The antero-lateral margins meet in front of the eye, but are not prolonged into a rostrum. The surface is smooth, or only very minutely punctulated; on either side there is a wide and rather deep incision in the antero-lateral margin, through which the antennules are visible; and the lobe beneath the sinus is triangular and subacute. Five free segments of the body are exposed, the first being very narrow and overlapped upon the sides by the carapace ; the second is longest, with the latero-inferior margins straight ; the third very short upon the dorsal surface, but, like the two following, produced backward at its postero-lateral angle. Similarly the first four postabdominal segments are produced backward on the sides, the produced portion forming a subacute lobe ; these segments are subequal, the fifth is longer, the sixth rather smaller than any of the preceding ; all are marked with longitudinal depressions on the dorsal surface, which are best visible in the dried specimens; the last segment or telson is represented only by an obscurely bilobate tubercle. The large black eye is placed immediately behind the frontal margin. The antennules, visible through the lateral sinus, are short and 5-jointed, the basal joint very short, the second longest and considerably dilated, the third dilated and shorter, the fourth slender and longer, and the fifth very small and ending in a pencil of setae. The first pair of legs are greatly elongated and slender, the extremity being clothed with a pencil of long seta?, which arise near the distal end of the penultimate joint; the fifth pair of legs is very short. The appendages of the first five postabdominal segments in the male are biramose; the rami flattened, ovate, and fringed at their distal extremities with long and flexible cilia; those of the sixth segment (uropoda) are fringed with short stiff setae along the inner margins of the base and the inner ramus, of which the two joints are subequal; in the outer ramus the basal joint is much shorter than the terminal. Length of animal (excluding appendages) not exceeding f inch. A good series of specimens of both sexes were collected at a depth of 40 fathoms in lat. 32° 41' N., long. 128° 57' E. ; one (a male) occurred at a depth of 50 fathoms, in lat. 33° 19' N., long. 129° 7|' E. ; and two males and a female were taken in lat. 32° 49' N., Ion"-. 128° 56' E. Var. GRANULATA. In two or three specimens (male and female), collected, with the typical form, in 40 fathoms, in lat. 32° 41' N., long. 128° 57' E., |