REPORT ON THE ASTEROIDEA. 395 
Chorological Synopsis of the Species. 
Ocean. Range in Fathoms. Nature of the Sea-bottom. | 
| ya wi =; a= Se zr i = | 
| Palmipes diaphanus . ; Pacific. | 150 Coral mud. | 
Palmipes membranaceus ; Atlantic. | 20 to 100 
Palmipes rosaceus : : Pacific and Indian. 
1. Palmipes membranaceus, Linck. 
Stella cartilaginea, Aldrovandus, 1602, De Animalibus Insectis, p. 743. 
Palmipes membranaceus, Linck, 1733, De Stellis marinis, p. 29, pl. i. No. 2. 
Asterias placenta, Pennant, 1777, British Zoology, vol. iv. p. 62, pl. xxxi. fig. 59a. 
Asterias membranacea, Retzius, 1783, K. Vet.-Akad. Nya Handl. Bd. iv. p. 238. 
Asterias cartilaginea, Fleming, 1828, Hist. Brit. Animals, p. 485. 
Anseropoda membranacea, Nardo, 1834, De Asteriis, Oken’s Isis, p. 716. 
Asteriscus membranacea, Miiller and Troschel, 1840, Monatsber. d. k. preuss. Akad. d. Wiss. 
Berlin, p. 104. 
Asteriscus palmipes, Miiller and Troschel, 1842, System der Asteriden, p. 39. 
Palmipes placenta, Norman, 1865, Ann. and Mag. Nat. Hist., ser. 3, vol. xv. p. 120. 
Locality.— Porcupine” Expedition : 
The Minch, 1869. Exact locality and conditions not recorded. 
2. Palmipes diaphanus, n. sp. 
Rays five. R=42 mm.; 7=25 mm. The minor radius is thus in the proportion of 
about 60 per cent. 
Rays comparatively well produced for the genus, sublanceolate or leaf-like in outline, 
the curvature of the contour having a graceful convexity laterally, and the extremity 
distinctly pointed. The body, which is extremely delicate and thin, is semi-transparent. 
An abruptly-rising rounded ridge proceeds along each radial line. 
The plates of the abactinal surface bear from three to five isolated tufts of small 
spinelets. Those in the median region of the disk bear four or five—three placed near 
the free margin (a larger one with a small one on each side), and one or two side by side, 
behind these. Beyond the central region and along the rays there are generally only 
three present, which are placed near the free margin. The larger tufts are composed of 
seven or eight short delicate spinelets, and the smaller tufts of five or six rather shorter 
ones. All the spinelets are microscopic and embryonic in character. 
The armature of the adambulacral plates consists of (1.) a series of six delicate elon - 
gate spinelets on the furrow margin ; and (2.) on the actinal surface of the plate a series of 
