BENTHESICyMUS TANI^ERI 



205 



i 



r 



I- 



Benthesicymus tanneri Fax. 



Flate IL 



m 



.EulL Mus. Comp. Zool., XXIV. 215, 1S93. 



Integument smooth^ membranaceous. Rostrum short, acute; laterally 

 compressed; raised above the orbit into a crest which is armed with two 



slender acute teeth ; the lower margin of the 



orbit is fringed with long 



closely set hairs. The rostral crest is continued backward as a sharp keel 

 on the median line of the carapace, as far as the cervical groove ; posterior 

 to this the carina is obsolescent. The lower angle of the orbit is prominent, 

 but not spiniforni; the branchiostegal spine is prominent, the pterygostomian 

 angle sharp but unarmed. The dorsal portion of the gastro-hepatic groove 

 is pronounced, and is followed by another obsolescent, transverse, cervical 

 furrow further back on the carapace, — a furrow which forms (he anterior 

 boundary of the cardiac area. The branchial area is bounded above by a 

 blunt ridge and is separated from the pterygostomian area by an oblique 

 suture. A slight carina runs from the branchiostegal spine to the branchio- 

 pterygostomian suture. The infero-Iatcral margin oi' the carapace is nearly 

 straight. 



+ 



Tlie first three segments of the abdomen are thick, rounded, and devoid 

 of dorsal carina or tooth ; the fourth segment is faintly carinatc but not 

 toothed ; the fifth and sixth are distinctly carinate and armed with a small 

 acute posterior tooth. The telson is short, convex above, and armed with 

 three pairs of minute lateral spines. 



The eye-stalks are about as long as the rostrum and have the form 

 characteristic of the genus ; the eyes are of a daik brown color. The basal 

 segment of the antennule is armed externally with a stylocerite which is 

 much shorter than the segment, and with a small acute spine at the distal 

 external angle. The antennnlar flagella are nearly as long as the body. 

 The second segment of the antenna is devoid of an external spine ; the 

 scale is broad, foliaccous, narrowed at the distal end ; the fiagellum is slen- 

 der and much longer than the body. The mcrus of the second maxillipcd is 

 long and narrow, its inferior distal angle not produced beyond the base of 

 the carpus; the exopod is much longer than the endopod, reaching forward 

 to the distal end of the antennal peduncle; it is fringed on both sides with 

 very long, delicate seta). The terminal segment of the endopod of the third 

 maxillipcd is flattened, truncate, and armed with about four strong spines on 



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