192 



DISCOVERY REPORTS 



•:•'».:• 



■:*;.':'■ 



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, i.e. 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 maintained as a species distinct from monoculoides . The presence of two serrations 

 on pleon segment 3 in the Australian specimen seems to imply that it should have been 

 referred to monoculoides. I do not consider the Australian "crassi" to be synonymous 

 with the true Atlantic crassi. Whether georgianus will prove to be really distinct from 

 crassi is a different matter. 



Fig. 116. Eusiroides georgianus, n.sp. a. Pleon 

 segment 3. b. Portion of integument highly 

 magnified, c. Telson, with apex of one lobe 

 highly magnified to show sculpture. 



Eusiroides stenopleura, n.sp. (Fig. 117 and PI. I, fig. 4). 



Occurrence: 1. St. 71. South-west Atlantic. 1^15 mm., 1 juv. 13 mm. 



2. St. 114. Bouvet Island. 1 ovig. 924 mm. 



3. St. 239. South-west Atlantic. 2 ?? 19 and 25 mm. Types. 



