262 Bulletin Vanderhilt Marine Miiseum, Vol. VII 



Genus: PAGURUS Fabricius 

 Pagurus cataphractus, new species 



Plate 103 



Type: This was collected by the yacht "Ara" at Lahaina, 

 Maui Island, Hawaiian Islands, December 12, 1928, and is de- 

 posited in the Vanderbilt Marine Museum. 



Distribution: Littoral zone of the Hawaiian Archipelago. 



Technical description : This species, which closely resem- 

 bles the older species, Pagurus setifer H. Milne Edwards, 1836, 

 known from many records in that great area extending from the 

 east coast of Africa to Japan, i. e., from about Long. 40° E. to 

 Long. 130° E. and from about Lat. 30° N. to Lat. 12° S., is dis- 

 tinctly separated therefrom by several definite characters. 



The carapace of Pagurus cataphractus Boone has the calci- 

 fied precervical portion about seven-eighths as wide anteriorly 

 as its median length ; the setigerous lateral margins are so little 

 divergent posteriorly that they appear nearly parallel ; the pos- 

 terior margin is defined by the usual cervical curvature, the dor- 

 sal surface being quite flattish ; the softer postcervical region is 

 about as long in the median line as the precervical, but has the 

 postlateral margins widely convex. The asymmetrical abdomen 

 has four wide, transverse calluses dorsally, well separated from 

 each other by wrinkled spaces covered by soft tough membranes, 

 each callus giving rise on the left margin to a uniramous pleopod, 

 consisting of a peduncle one-half as long as the related elongate, 

 narrowly oval, setigerous, distal blade, which is not quite one- 

 half so long as the width of the related callus. The asymmetrical 

 rhipidura is larger on the left side ; the transversely articulated 

 telson is rectangular, the proximal portion being slightly longer 

 than the distal, and the distal margin slightly convex. 



The eyestalks are depressed cylindrical, moderately dilated 

 distally and about four-fifths as long as the anterior margin of 

 the carapace ; they exceed the length of the antennular peduncle 

 by slightly more than the length of the cornea and similarly are 

 longer than the antennal peduncle. The cornea, which are ter- 

 minal on the dilated stalks, fully occupy the distal fourth thereof, 

 being dorsally of less depth than ventrad. 



