30 Bulletin Vanderhilt Marme Museum, Vol. V 



pairs of longitudinal carinae. The pair of submedian longitudinal 

 carinae extend from the third thoracic segment to the posterior 

 margin of the sixth thoracic segment, these carinae being less empha- 

 sized but distinct on the first visible thoracic segments; and on the 

 fifth and sixth abdominal segments the carinae terminate posteriorly 

 in a small acute spine; the carinae of the sixth segment are much 

 thicker than elsewhere. A second pair of carinae, the upper lateral 

 carinae, extend from the third thoracic segment to the posterior mar- 

 gin of the sixth segment, subparallel to the median and lower lateral 

 carinae, which latter begin on the rounded process of the first ab- 

 dominal segment and extend to the hinder margin of the sixth seg- 

 ment, where they are in line with the heavily carinate outer lateral mar- 

 gin of the telson ; these carinae are thicker than either of those above 

 and terminate on the fourth to sixth segments inclusive in a small 

 spine posteriorly. The telson is shield-shaped, nearly as wide distally 

 as proximally, with a very strong, triangulate median carina, which 

 has two small bosses proximally, one on either side; there is also an 

 indentation on the surface of the carina near its base ; the distal end 

 of the carina is a small spine and below it there is a large round 

 tubercle. The lateral margin of this triangulate carina is outlined 

 on either side by a pair of large punctae and radiating out from this 

 line there are ten or eleven curved lines of punctae, evenly spaced and 

 extending to the marginal carinae. Similar lines of punctae ornament 

 the ventral surface of the telson. The distal margin of the telson is 

 shallowly incised by a linear sinus, on either side of which there are 

 three crenulations or small teeth, followed by the short, thick, sub- 

 median carina, which is tipped by a strong spine. There are eight 

 small denticles between this submedian carina and the distal lateral 

 carina, which is short and thick, terminating in a very strong spine. 

 At its base is a small denticle, followed by the median lateral carina, 

 which is thick, terminating in a sharp spine and has immediately 

 behind it the subequal proximal carina which also terminates in a 

 short spine. 



The uropoda have the peduncle strong with a small spine on the 

 distal upper angle and two longitudinal carinae on the upper surface, 

 the anterior one short and faint and the posterior one stronger and 

 extending to the tip of the longer spine of the produced process. 

 There is also a strong longitudinal carina on the ventral surface of 

 this spine. This process is very strong and curved, its inner lateral 

 margin being very concave and coarsely crenulate; the very acute 



