III. Rocinela cornuta, sp. nov. Figs. 1, 2. Length of body, two and one-quarter times its greatest breadth. Outline, oval; surface smooth, with scattered points of depression. Head subtriangular, having a medium excavation. Its frontal margin is produced forward in a long and broad projection, widely rounded at its extremity, and curving upward. Eyes large and situated at some distance apart. The first antenna reaches the anterior margin of the first thoracic segment; its flagellum contains six articles. The second antenna extends to the posterior margin of the second thoracic segment; its flagellum is sixteen-jointed. FIG. I.-Head, X I. The thoracic segments are subequal. The antero-lateral angles cor FIG. 2.-a. Rocinela of the first segment are greatly produced and extend forward a little less than half the length of the head, including the projection. These antero-lateral projections of the first segment do not follow closely the lines of the head, but rather extend out straight in a direction which is parallel to that of the frontal projection of the head. The extremities of these projections are rounded. The epimera of all the segments point downward and do not extend beyond the post-lateral angle of their respective segments with the exception of the sixth and seventh ones. The first segment of the abdomen is almost entirely covered by the seventh thoracic segment. The last segment is rounded posteriorly and is faintly crenulate. The two branches of the uropods are similar in shape and size; the inner branch, being the longer, reaches the extremity of the abdomen. The uropods as well as the abdominal segment are furnished with hairs. The propodus of the prehensile feet is armed with three spines, and three blunt ones are found on the merus. The gressorial feet are long and slender and covered with spines. Type.-The type specimen was found off Shumagin Bank, Alaska, Station 3338, 625 fathoms (U. S. Nat. Mus., No. 20086). Rocinela cubensis, sp. nov. Figs. 3, 4. Outline of body oval, surface smooth. FIG. 3.-Head. Head with rounded lateral margins. Its anterior margin is produced forward in a large rounded projection, whose breadth is equal to its length, and whose upper surface is deeply concave with upturned edges. This projection extends forward for about half its length and then upward, the change in direction being gradual. Eyes large and composed of ten rows of ocelli. Two small tubercles are situated between the eyes, and in the middle of the head and back of these is an arc-shaped depression. The first antenna reaches the posterior margin of the head; its flagellum contains six articles. The second antenna extends to the posterior margin of the third thoracic segment; its flagellum contains fifteen articles. The thoracic segments are subequal in length. The epimera are long and narrow, with very acute posterior angles. The first segment of the abdomen is almost entirely concealed by the last thoracic segment. The fifth is likewise covered at the sides by the fourth segment. The last abdominal segment is triangular in shape with a rounded posterior margin. The outer branch of the uropods is very broad and oar-shaped, with a rounded extremity. The inner branch is long and slender, of equal breadth throughout its length and rounded on its posterior margin. The inner branch is the longer one. Both are fringed with hairs. In the prehensile legs of this species the basis presents a row of tubercles on its superior margin. two spines on this propodus and three on the merus. sorial legs are but slightly spinulose. FIG. 4. a. Rocinela cubensis, J, X 24. b. Leg of first pair, X 4. c. Leg of fourth pair, X 4. There are The gres Type.-The type specimen was found off Havana, lat. N. 23° II', long. W. 82° 19' 6", Station 2341, 143 fathoms (U. S. Nat. Mus., No. 20087). Rocinela laticauda, Hansen' Fig. 5, 6. Head, with a median projection, long and broad, extending slightly downward and having a blunt extremity. Eyes large, with ten rows of ocelli. The first antenna, with a flagellum containing six articles, reaches the posterior margin of the head. The second antenna extends to the middle of the FIG. 5.—Head × 23. second thoracic segment; its flagellum contains fifteen articles. The thoracic segments are equal in length. The first is deeply bisinuated, its antero-lateral angles extending up the side of the head to about the middle of the eyes. The epimera of the second, third and fourth segments are rounded posteriorly; those of the remaining segments have pointed extremities. The first segment of the abdomen is almost entirely covered by the last thoracic segment. The fifth segment, as well as this one, is narrower than the intervening segments, and not as broad as the base of the terminal segment. The last segment is widely rounded posteriorly and is fringed with rough hairs which almost conceal its crenulated margin; at the base it is impressed on either side of a keeled centre; the outer branch of the uropods is almost twice as broad as the inner branch; they are about equal in length. Both are fringed with hairs and indistinctly crenulate. The prehensile legs are stout and short. ticauda, ♂, slightly There are four spines on the propodus and reduced. b. Leg of first five on the merus, besides numerous hairs. C FIG. 6.-a. Rocinela la pair, X 4. c. Leg of The gressorial legs are likewise stout and fur fourth pair, X 4. nished with spines and hairs. 1 The description of the above species was written and the drawings made when Dr. Hansen's type specimen was returned to the U. S. Nat. Mus., and his manuscript sent to the press. As there are a few differences in the specimens, it was thought best to publish the new description. The specimen described came from Alaska, off Unimak Island, Station 3225, 85 fathoms (U. S. Nat. Mus., No. 20088). Distribution.-One specimen was found off San Luis Obispo Bay, California, Station 3195, 252 fathoms; one off Esteros Bay, California, Station 3194, 92 fathoms, and another at Puget Sound, Washington, Station 3067, 82 fathoms. The specimens from the coast of California are smaller in size and of very much lighter color than the other specimens. They are similar in other respects. Dr. Hansen's type specimen is from Acapulco, Mexico, Station 3418. It differs from the specimen herein described in the length of the second pair of antennæ, which extend to the middle of the third thoracic segment, while in the specimen we have described they extend only to the middle of the second thoracic segment; in the broader and longer terminal segment of the body, and in the increased number of spines on the propodus, and the decreased number of spines on the merus of the prehensile legs. Rocinela japonica, sp. nov. Fig. 7–9. Surface of body punctate and covered with black or brown dots. Color yellow, marked lightly in such a way as to present a mottled appearance. At the base of the terminal segment of the body, there are two small spots of brown, separated by a distance equal to half the width of the segment. Head subtriangular, excavated in the centre between the eyes and having the lateral margin in front of the eye produced into a lobe; the extreme front being truncate with rounded angles and curving slightly upward. The lobe in front of the eye extends half way between the eye and the extreme front. The eyes, which are small, are separated by a distance of half the width of the head. The first antenna, with a flagellum of six joints, reaches the posterior margin of the head. The second antenna, with a flagellum of fifteen joints, extends to the posterior margin of the second thoracic segment. FIG. 7. Head, X I. The epimera of all the segments of the thorax are acute, the posterior angles more rounded in the first two, but sufficiently pointed, in the remaining four. The epimera of the last two segments take a more oblique direction than the preceding ones, and extend laterally as far as the outer margins of the abdominal segments. The The first abdominal segment is almost entirely covered. posterior angles of these segments are very acute and are produced at the sides beyond the terminal segment and the basal joints of the uropods. The terminal segment is linguate and obscurely crenulate FIG. 8. Rocinela japonica, J, X I}. on its posterior margin. The internal branch of the uropods is somewhat longer than the external one, but the two are equal in width. They are both armed with spines on their outer margins. The prehensile legs are slender. There are three or four hair-like spines on the propodus and five blunt ones on the merus. The gressorial legs are likewise slender and spinulose. Of this species a single individual was found at Hakodate Bay, Japan, Station 3659, depth fifteen and a half fathoms (U. S. Nat. Mus., No. 20651). This species is closely related to R. modesta Hansen. It differs from that species in the length of the first pair of antennæ, which extend only to the middle of the last joint of the peduncle of the second pair of antennæ, while in R. modesta Hansen they extend a little beyond the peduncle of the second pair of antennæ; in the greater development of the lateral margin of the head in front of the eye into lobes; in the excavation in the frontal area of the head; in the extreme front being directed upward; in the number of spines on the FIG. 9.-Leg of first merus of the prehensile legs, five spines being pair, X 3. Leg of characteristic in our species, three or four in Dr. fourth pair, X 3. Hansen's species; in the markings on the surface of the body of small black dots and the presence of two larger spots at the base of the terminal segment of the body. Rocinela tuberculosa, sp. nov. Fig. 10. Surface of body punctate and marked with small black dots. The posterior margin of each of the thoracic and abdominal segments is lined with a row of tiny tubercles, above which is a row of small black dots. Head subtriangular, rounded in front. Eyes large and situated at a distance of one-third of the head apart. The first antenna, with a flagellum of five articles, FIG. 10.-Roci- reaches the posterior margin of the head; the second nela tubercu- antennæ extends to the posterior margin of the second losa,,X2 thoracic segment; its flagellum contains eleven articles. |