STALK-EYED CRUSTACEA 305 



Antero-lateral and postero-lateral margins continuous ; 

 the latter armed with a strong tooth about its middle. 

 Fronto-orbital region very broad, occupying more than 

 one-half the width of the carapace. Eyes large. Th.c 

 external maxillipedes not reaching the anterior extremity 

 of the buccal area; third joint truncated in front, without 

 projecting at the inner angle, which, like the outer one, is 

 a right angle ; fourth joint, shorter and broader than the 

 third, is narrowed in front, with the next joint articulating 

 with it at its antero-internal angle; external appendage 

 reaching tip of fourth joint. First pair of legs with a 

 great spine on its fifth joint in a horizontal plane, project- 

 ing outwards transverse to the axis of the body. Walking 

 feet with slender terminal joints. 



Range. — West Indian Sea ; in deep water. 



Synopsis of the Species. 



A. Postero-lateral marginal tooth very long, and pro- 

 jecting laterally outwards. — (A. bispinosiis?) 



B. Postero-lateral marginal tooth short, and projecting 

 backwards. — {A. alexandri.) 



I. Acanthocarpus bispinosus. 



AcantJwcarpus bispinosiis . . A. Milne Edwards. 



The carapace circular, with a long well-developed 

 lateral spine directed outwards, behind which, on the 

 border of the carapace, there is a series of small teeth. 

 The rostral tooth is long. The external maxillipedes 

 have, outside, a fringe of hairs. The sternal plastron has 

 no lateral groove upon its first articulation. 



Range. — Grenadines. 

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