IGG BULLETIN OF THE 



gracilis was obtained in 2435 fathoms. A young Ili/ocrinus (1) was 

 dredged by the " Challenger " in 2325 fathoms, while Antedon was found 

 at 2600 and at 2900 fathoms. 



So far as I am aware, no entire Pentacrinus was obtained by the 

 " Blake " at a greater depth than 250 fathoms,* while six of the " Chal- 

 lenger" species were found within that limit; though the "Poi'cupine" 

 dredged P. u^yville-thomsoni in 1095 fathoms in 1870, and the "Chal- 

 lenger " got a fragment of P. naresianus Wy. Th. MS., in the Pacific, at 

 1350 fathoms, this being the deepest Pentacrinus yet known. Bathy- 

 crinus, however, ranges from 1050 to 2435 fathoms, and Hyocrinus from 

 IGOO to 2325 fathoms, while RJdzocrinus lofotensis occurs in the Norwe- 

 gian fiords at 80 fathoms, and in 175 to 955 fathoms in the Caribbean 

 Sea, It is a great pity that we have no later knowledge of the " Austra- 

 lian Eucrinite " on a stem G" long, which was obtained by Poorc f at a 

 depth of 8 fathoms in King George's Sound. 



It is well known that thi'ce genera of Stalked Crinoids occur in the 

 Caribbean Sea besides the three Comatukt:\; viz. Pentacrinus, IIolopus, 

 and llhizocrinus. The last-named is represented by two species, and the 

 first by four, viz. P. asteria Linn, sp., /■*. miilleri Oerst., P. decor us Wy. Th., 

 and /-*. blakfi n. sp. The first of these, which is the type species of the 

 genus, seems never to have been dredged by the " Blake," except per- 

 haps in a fragmentary state. It is mentioned, however, by Mr. Agassiz § 

 as having been dredged off Havana in 1878, but the individuals there 

 referred to really belong to P. miilleri ; while the very variable form with 

 a slender stem, which Mr. Agassiz and the late Mr. Pourtales have 

 spoken of as P. miilleri, is really the P. decorus of Sir Wyville Thomson. 

 These two species have hitherto been confused with one another, and it 

 is only since I have been able to examine the original types of them in 

 the Copenhagen and British Museums respectively, that I have succeeded 

 in forming clear ideas aboiit them. The relations of the Caribbean 

 species to one another, and to the other species of the genus, are shown 

 in the following scheme. 



o 



* Spr-cimcns were obtained in as little as 42 fathoms, and stein fragments down 

 to 470 fathoms. 



t Ann. and Mag. Nat. Hist. (]S()2), Voh IX. p. 486. 



t Antedon, Adinomdm, and Atdccrinus. See Bull. Miis. Comp. Zool., Vol. IX. 

 Xo. 4. 



§ Bull Mus. Comp, Zoul., Vol. V. No. 6, p. 56. 



