678 



poda scarcely differing in their structure from those limbs in the genus Ari><tia.i 

 Telson, however, rather different, being entire, without any cleft. Sexua 

 difference very slight. 



Remarlis. — The present genns was established in the year 1892 l)i 

 MM. Chevreux and Bouvier, to include a form, which at first was believed t| 

 be new to science, but was subsequently shown by M. Bonnier to be the trui 

 Lysianassa audouiniana of Sp. Bate. In the same year, though perhaps a littln 

 later, Mr. Robertson examined tlie same form, and proposed for its receptiot 

 the new genus Pararistias. The genus is indeed very closely related to Arh 

 stias, but may perhaps be retained on account of some differences occurrin^f 

 in the structure of the oral parts, and especially on account of the very 

 differently shaped telson. It contains as yet but a single species, to be d 

 scribed below. 



c 



Perrierella audouiniana. (Sp. Bate). ! 



(Suppl. PI. II, fig. 2). . I 



Lysianassa audouiniana, Sp Bate, Catal. of Ampli. Brit. JIus., p. 69, PI. XI, lig. 1. i 



Syn. : Aristias audouiuianus, Jleinert. 



» Perrierella erassipes, Chevreux i^ Bouvier. 



Pararistias audouiuianus, Robertson. 



I 



Body short and compact, with broadly rounded back. Cephalon abouti 

 the length of the 1st segment of mesosome and rather deep, with the anterior 

 edges somewhat convex, lateral corners slightly produced at the tip. Anterior 

 pairs of coxal plates scarcely as deep as the corresponding segments; 1st pair 

 small, and to a great extent covered by the 2nd, which are of a rounded 

 oval form, with the distal edge slightly serrated; 3rd pair somewhat expanded 

 distally; 4th pair of an irregular rhomboidal shape; the 2 succeeding pairs 

 much smaller, and having the posterior lobe deeper than the anterior. Last 

 pair of epimeral plates of metasome angularly produced at the lateral corners. 

 Urosome short and stout. Eyes rather large, and of a somewhat oval form, 

 being slightly narrowed above, pigment dark, with a chalky white coating. 

 Superior antennae about the length of the cephalon and the first 2 segments 

 of mesosome combined, joints of the peduncle rapidly diminishing in size, 

 flagellum much shorter than the peduncle, and composed of 4 articulations 

 only; accessory appendage rather small, biarticulate. Inferior antennse with 

 the flagellum very small, not even attaining the length of the last peduncular 

 joint, and 4-articulate. Anterior gnathopoda rather strong, propodos exceeding 



