. Allan Hancock Pacific expeditions. [Reports]. Scientific expeditions. NO. 2 ZIESENHENNE: NEWOPHIURANS 39 The name irregularis has been chosen for this species because of the irregular arrangement of the disk scales. Amphiophiura paucisquama, new species Plate 8, Figs. 1-3 Description.—Disk diameter, 7 mm.; thickness of disk, mm.; arms, 13 mm. long. Disk large, arms relatively short, tapering rapidly. Disk covered with 21 very large pitted plates including the radial shields. A large, swollen, pentagonal central plate is surrounded by 5 slightly larger plates that are in contact with the
. Allan Hancock Pacific expeditions. [Reports]. Scientific expeditions. NO. 2 ZIESENHENNE: NEWOPHIURANS 39 The name irregularis has been chosen for this species because of the irregular arrangement of the disk scales. Amphiophiura paucisquama, new species Plate 8, Figs. 1-3 Description.—Disk diameter, 7 mm.; thickness of disk, mm.; arms, 13 mm. long. Disk large, arms relatively short, tapering rapidly. Disk covered with 21 very large pitted plates including the radial shields. A large, swollen, pentagonal central plate is surrounded by 5 slightly larger plates that are in contact with the single, large, interradial plate and the radial shields. The interradial plate is pentagonal with the proxi- mal margins concave, forming a peak, lateral and distal margins almost straight. Viewed under an ordinary hand lens all plates are deeply pitted, resembling the mesh on a golf ball. Radial shields much smaller than disk plates, pentagonal, fully in contact, decidedly broader than long, deeply pitted as other disk plates. First upper arm plate oval, broader than long, fully in contact with the second arm plate and radial shields, lateral margins bear genital slit papillae. Distally the plate bears an elevated transverse ridge which is deeply pitted. Second plate oval, broader than long, with a high convex surface, deeply pitted, in contact with the first upper arm plate. Third plate oval, slightly broader than long and rather high, elevated to re- semble a golf ball, deeply reticulated. Succeeding plates diamond shaped, becoming smaller, flatter, and more widely separated by the side arm plates distally. Side arm plates twice as broad as long, swollen, in contact below from the 5th arm segment out and in contact above from the 3rd segment out. Three short, peglike arm spines about Yz the length of the side arm plates, widely separated, upper longest and heaviest, under short- est. The arm plates are separated from each other or appear that way be- cause of the prominent
Size: 1748px × 1430px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectio, booksubjectscientificexpeditions
