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DESCRIPTIOX 

 Of a Kew Animal belonging to the Crustacea, discovered in 

 the Antarctic Seas, by the author, James Eights. 



[CalDinet of the Albany Institute.] 



GENUS GLYPTONOTUS. (Eights.) 



Animal composed of a head, thorax, and post-abdomen 

 or tail, constituting in all thirteen distinct segments. 



Head deeply inserted into the cephalic segment of the 

 thorax. Eyes sessile, and finely granulate. Antmnd two 

 pairs, placed one'above the other, with an elongate multi- 

 articulated filament. Mouth as; in the ordinary Isopods, 

 mandibles not palpigerous ; the two superior foot-jaws 

 expanded into a well defined lower lip, beariiiij; palpi. 



Thorax separated into seven distinct sej^im-uts, tlie three 

 posterior ones biarticulate near their lateral extremities ; 

 each segment giving origin to a pair of perfect legs, ter- 

 minating with a strong and slightly curved nail. 



Post-abdomen, or tail, divided into five segments, provi- 

 ded with neither styles nor swimmerets ; the under sur- 

 faces each supporting a pair of branchial leaflets, longitu- 

 dinally arranged, and covered by two biarticulated plates 

 attached to the outward edges of the last segment, closing 

 over them much in tlie manner of an ordinary bivalve 

 shell. 



SPECIES G. ANTARCTICA. (Eights.) 

 Antarctic Sculpture- back. 

 Animal perfectly symmetrical, ovate, elongate, and de- 

 pressed. Teguments solid and calcareous. Color, brown 

 sepia. Length, from the insertion of the antennae, three 

 and a half inches ; width, one and three-quarters. 



Head transversely elliptical, terminating at its lateral 

 and anterior corners acutely, and incurved ; anterior mar- 

 gin obtusely elevated, and arched each way to its centre. 



