8 Messrs. E. W. L. Holt and W. M. Tattevsall 



Katenjthrops Oceana^, II. & T. (PL I.) 



Form robust. Carapace much wider than the pleon, 

 almost entirely coA'eriiig the thoracic segments ; anterior 

 mai'giu obtusely rounded ; cephalic region inflated and poste- 

 riorly defined by a well-marked cervical sulcus. Pleon with 

 the last segment almost as long as the two preceding segments 

 taken together. Eyes small, remote from each other, sub- 

 pyriform, the proximal part the broader; A'isual area 

 restricted to less than the distal half; cornea not so wide as 

 the last joint of the antennular peduncle ; pigment after 

 preservation in formalin reddish buff. Peduncle of antennule 

 at least a fifth longer than the last segment of the pleon, 

 proportionally stout, its last joint about equal to the two 

 preceding, beset dorsally between the insertions of the 

 flagella with a bidentate tubercle, of which the denticles are 

 nearly in the same dorso- ventral plane. Ante7inal scale very 

 short, narrow, and. somewhat outwardly curved ; outer margin 

 entire, naked, terminating in a feeble spine; apex produced 

 considerably beyond the spine, subacute, setae confined to 

 the apex and to about the distal third of the inner margin ; 

 length of scale more than four times (about ^) the greatest 

 width, slightly less than the combined length of the last two 

 joints of the antennal peduncle, and but little exceeding the 

 length of the last joint of the antennular peduncle. An- 

 tennal peduncle long and proportionally stout, combined length 

 of the last two joints greater than that of the last joint of 

 the antennular peduncle. 



Exopodites of the thoracic limbs very well developed, with 

 unusually large flagella. Endopodites of the first four pairs 

 moderately long and stout ; the tarsus in the third and 

 fourth pairs consisting of three joints, and succeeded by a 

 well-developed dactylus ; setae not more plumose than in 

 Parerythrops &c. Pleopods of all five pairs biramous in the 

 male, the inner ramus bifid. Telson subtriangular, shorter 

 than the last segment of the pleon by about two sevenths of 

 the length of the latter, its sides entire and slightly inflected ; 

 apex narrowly truncate, armed with two pairs of rather 

 slender spines, of which the inner are considerably the longer 

 and stouter ; a median pair of setae possibly present. Outer 

 iiropod the longer, its length including basal articulation 

 slightly greater than the combined length of the fifth and 

 sixth segments of the pleon. Length of the type specimen 

 (an immature male) 6 mm., including antennular peduncles 

 and uropods. 



