[19] 



DECAPOD A FROM ALB ATE OSS DREDGINGS. 



363 



PONTOPHILUS ABYSSI, Sp. DOV. 



This species is closelj^ allied to P. gracilis (Bull. Mns. Comp. Zool., Cain- 

 bridge, X, p. 3C, pi. 7, figs. 2, 3, 1882), but is readily distinguished by 

 the smaller and nearly colorless eyes, and by having two spines in place 

 of one on the gastric region. 



The carapax, including the rostrum, is more than twice as long as 

 broad in the male, but broader proportionately in the female, and 

 slightly carinated. The rostrum is about a fifth as long as the rest of 

 the carapax, very slender, and armed near the base with two minute 

 lateral teeth each side. There are three spines on the median line, two 

 near together on the anterior part of the gastric region and one on the 

 anterior part of the cardiac, and between the posterior gastric and car- 

 diac spines the dorsal carina is very distinct, but not high. As in P. 

 gracilis^ there is a distinct hepatic spine and above and back of this 

 another in the obscure lateral carina, but in addition there is a minute 

 spine each side just back of the supraorbital fissure. 



The eyes do not reach to the tip of the rostrum, are only very slightly 

 compressed vertically, little more than half as large proportionately as 

 in P. gracilis, the diameter being about a tenth the length of the cara- 

 pax, and colorless in alcoholic specimens. 



The characters of the articular ajjpendages in general and of the pleon 

 are so nearly like those of P. gracilis that further description is unnec- 

 essary. The number and arrangement of the branchiai is the same as 

 in P. Norvegicus and brevirostris, and as in the species of Babinea. 



Measurements in millimeters. 



station 



Sex 



Length from tip of rostrum to tip of telson 



Length of carapax, including rostrum 



Length ot rostnim 



Breadth of carapax 



Greatest diameter of eye 



Length of antennal scale 



Breadth of antennal scale 



Length of first periEopod 



Length of chela 



Length of dactylus 



Length of second peraeopod 



Length of third peraeopod 



Length of merus 



Length of carpus 



Length of propodus 



Length of dactylus 



Length of fourth peraeopod 



Length of merus 



Length of carpus 



Length of propodns 



Length of dactylus 



Length of sixth somite of pleon 



Higut of sixth somite of pleon 



Lengtli of telson 



Lengt h of inner lamella of uropod 



Breadth of inner lamella of uropod 



Length of outer lamella of uropod 



Breadth of outer lamella of uropod 



2098 



2097 



d 



47.0 



13.5 

 2.2 

 0.0 

 L3 

 7.5 

 2.0 



16.0 

 6.1 

 2.5 

 7.0 



20.0 

 5.0 

 5.7 

 3.2 

 1.7 



19.0 

 4.5 

 2.6 

 4.0 

 2.6 

 8.0 

 3.0 

 9.0 

 7.3 

 1.5 

 6.8 

 2.0 



? 



53 + 

 15.0 



2.4 



L6 

 8.5 

 2.2 

 19.0 

 7.0 

 2.9 

 9.0 



9.5 

 3.5 



9.0 

 1.7 

 8.4 

 2.3 



