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BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM 



has the sixth joint subdivided into eight subjoints. (6) The telson 

 (fig. 91, b) is linguiform in shape, three times as long as broad at the 

 base, apex bluntly rounded ; the lateral margins are armed with short 

 blunt spines which are grouped into series in the center third of the 

 margin ; apex armed with a closely set row of short blunt spines, all 

 equal in size and set like the teeth of a saw. (7) The inner uropod has 

 no spines on the lower margin near the statocyst. (8) The fourth 

 pleopod of the male (fig. 92, /) of curious form, rather short and 

 stout, exopod three (?)-jointed, curved, with two very stout and 

 heavily barbed setae, one at the tip and the other arising from the 

 inner corner of the penultimate joint, outer margin of the exopod with 

 about seven long simple setae. 



Figure 91. — Acanthomysis pseudomacropsis (Tattersall) : a, Anterior end to show rostral 

 plate, eye, antennal scale, and antennular peduncle, X 22}£; b, telson, X 25. 



This species is closely allied to A. macropsis but differs from it in 

 the shorter eye, longer antennal scale, the presence of a spine on the 

 labrum, the absence of spines on the inner uropod, and in the propor- 

 tions of the telson. The fourth pleopod of the male is very distinctive 

 and enables males to be readily recognized. 



ACANTHOMYSIS LONGICORN1S (Milne-Edwards) 

 Mysis longicornis Milne-Edwabds, 1S37, p. 459 ; 1840, pi. 26, figs. 7-9. 



Occurrence. — Naples*, identified by A. M. Norman. 

 Distribution. — The Mediterranean Sea and Atlantic coasts of 

 Europe. 



ACANTHOMYSIS sp. ? 



Reference to this species may be found on page 249. 



