. â¢:â¢'».:⢠â :*;.':'â Maxilla i, 3-4 setae on inner lobe. Maxilla 2, inner lobe broader than outer, without any submarginal oblique row of setae. Telson twice as long as basal width, cleft for just over half its length, the lobes tapering evenly to acute entire apices, one or two long upstanding simple setae on lateral margin at about two-thirds or three- quarters the length (absent in no. 5). Under a high magnification the surface appears covered with very fine transverse lines. In the embryo from the brood-pouch the telson resembles that of the adult in shape and extent of the cleft. Int
. â¢:â¢'».:⢠â :*;.':'â Maxilla i, 3-4 setae on inner lobe. Maxilla 2, inner lobe broader than outer, without any submarginal oblique row of setae. Telson twice as long as basal width, cleft for just over half its length, the lobes tapering evenly to acute entire apices, one or two long upstanding simple setae on lateral margin at about two-thirds or three- quarters the length (absent in no. 5). Under a high magnification the surface appears covered with very fine transverse lines. In the embryo from the brood-pouch the telson resembles that of the adult in shape and extent of the cleft. Integument very minutely shagreened, with scattered pits; under a high magnification by transmitted light very fine more or less parallel lines are visible as in the enlarged portion of the telson figured here. Eyes reniform, nearly contiguous dorsally. Remarks. It would be easy to regard this form as a variety of crassi, which was taken farther north off Monte Video in 600 fathoms; or perhaps to regard the combination of a pleon segment 3 with only one notch, together with the palm of gnathopods as in crassi, as an argument for uniting the "triumvirate " caesaris,pompeii and crassi. Between a sinus and a serration there would seem to be but little difference; yet there is a difference and it would not be quite correct terminologically to describe the sinus of pleon segment 3 in the. present specimens as a single serration (cf. the figure here given with Stebbing's figure of the pleon segment 3 in caesaris or pompeii, 1888, pis. lxxxviii, lxxxix). Typical crassi has no suggestion of either a sinus or a serration (cf. Stebbing, 1888, pi. xc). The telson is much more deeply cleft than in typical crassi. In the above comparison I have referred throughout to typical crassi, the Chal- lenger specimen from off Monte Video. This is necessary because Stebbing himself has recorded crassi from South-east Australia and expressed doubt as to whether crassi can be main
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
