REPORT ON THE CRINOIDEA. 33 



four species of Antedon, three of which were each found at two or more different stations. 1 

 Thus Antedon abyssicola, from 2900 fathoms (Station 244) in the North Pacific, also 

 occurs at 2600 fathoms (Station 160) in the Southern Sea; and the remaining abyssal 

 station south of lat. 40° S. (Station 147, 1600 fathoms), yielded three different species 

 of the ten-armed Antedon-type. The species dredged at Station 135e in 1000 fathoms 

 was only represented by Pentacrinoid larvae, but of the eight remaining abyssal forms 

 (found below 700 fathoms), one that occurred at four stations in the Pacific is closely 

 allied to Antedon tenella, which ranges down to 740 fathoms in the North Atlantic, 

 between 30° N. and 75° N.; while three others belong to the same group as this species 

 and Antedon rosacea, which ranges in shallow water from the Fseroe Banks to the 

 Canary Islands, and possibly even to the equator. 



In like manner, the Magellan and Heard Island species from the furthest south are 

 the Antarctic representatives of Antedon eschrichti and Antedon quadrata, which are 

 widely distributed in the Arctic Ocean. In fact, the group to which these forms belong 

 has the greatest geographical range of any set of the ten-armed Antedon-type,. 



Antedon eschrichti (PI. XXIV. fig. 11) and its close ally Antedon quadrata 

 (PI. XXVI. figs. 2, 3), are common in the Arctic Ocean between the meridians of 80° W. 

 and 70° E. They were found by the " Porcupine " in the Fseroe Channel, and by the 

 Challenger off Halifax, which is their furthest southern range (lat. 43° N.). No other 

 Comatulae but the dimorphic Antedon lusitanica were found in the North Atlantic below 

 650 fathoms, but this form does not at all approach the Eschrichti-gvowp. The Straits 

 of Magellan, however, contain two species belonging to it ; while Antedon australis, and 

 Antedon antarctica from the neighbourhood of Heard Island are also very closely 

 allied to, though not identical with Antedon quadrata and Antedon eschrichti, and 

 are the southernmost Comatuhe known (PI. XXV.; PI. XXVI. fig. 4). None of these 

 species, however, nor in fact any of the Eschrichti- group, extend down to any greater 

 depth than 650 fathoms; but some of the Comatulse from depths below this belong, as 

 we have seen, rather to the North Atlantic than to the Arctic fauna. Certain of them, 

 however, find their places in the group of ten-armed species which have the sides of the 

 rays flattened and more or less closely approximated. One of them {Antedon bispinosa, 

 PI. XX. fig. 3) was obtained at Station 147, together with two species of the Tenella- 

 group, and two others {Antedon acutiradia and Antedon breviradia, PI. XL figs. 3, 5) 

 were the only two dredged with certainty at Station 175.' 2 All these three occurred 

 below 1300 fathoms. 



With the exception of Antedon bisjnnosa from the Southern Sea and Antedon 

 lusitanica and Antedon multispina of the Atlantic, all the twenty forms with laterally 

 compressed rays {Basicurva-growp) inhabit the Western Pacific and Australasia; and only 



1 The Antedon breviradia and Antedon alternata occurred both at 630 and 1070 and at 1350 fathoms respectively. 

 ■ See ante, p. 32. 

 (ZOOL. CHALL. EXP. — rABT LX. — 1888.) Ooo 5 



