330 



THE VOYAGE OF H.M.S. CHALLENGER. 



A. Three distichals, not succeeded by palniars. 



I. Ten to twenty cirri, generally with less than fifteen joints. 



(a) Arm-joints triangular till some distance from the disk, and con- 



siderably wider than long, ..... 



(b) Arm-joints relatively long, becoming quadrate about the fifteenth, 

 II. Thirty or more cirri of fifteen to twenty joints. 



(a) Arm-joints short; lower joints of distichal pinnules not specially 



marked, ....... 



(b) Arm -joints of moderate length; lower joints of distichal pinnules 



rather large and carinate, ..... 



B. Palmar series developed above the distichals. 



I. Two palmars, the axillary not a syzygy. 

 (a) Post-palmars like palmars. 



1. Ten cirri, ...... 



2. Twenty cirri ; one or two further divisions, like palmars, . 

 (6) Post-palmar series of three joints, the axillary with a syzygy. 



1. Fifty cirri on a hemispherical centro-dorsal, 



2. Centro-dorsal reduced, with few or no cirri. 



a. Further division like palmars; centro-dorsal stellate, 

 /S. Further division like post-palmars. 

 (i.) Fifteen to twenty small cirri, . 

 (ii.) Centro-dorsal stellate, without cirri. 



Rays well separated ; mouth radial, . 

 Rays closely united, and the interradial peri- 

 some plated ; mouth interradial, . 

 II. Palmar series at outside of ray two-jointed, without a syzygy ; the inner 

 series three-jointed, with a syzygy. 

 (a) Post-palmars of two joints, the axillary not a syzygy ; pinnule 

 joints carinate, ...... 



(6) Post-palmars of three joints, the axillary with a syzygy. 



1. Fifteen cirri ; rays quite free, .... 



2. No functional cirri ; rays closely united, . 

 III. Three palmars, the axillary with a syzygy. 



a. No further division. Centro-dorsal bears functional cirri. 



1. Ten to twenty -five cirri, generally with less than fifteen 



joints, ...... 



2. Thirty or more cirri, of fifteen to twenty joints. 



(a) Lower pinnules not specially large. 



Arm-joints short ; lower joints of distichal pin- 

 nules not carinate, .... 



Arm-joints of moderate length ; lower joints of 

 distichal pinnules rather large and carinate, . 



(b) Distichal and palmar pinnules very large and stout, 



b. Post-palmar series present. 



1. No functional cirri ; post-palmars of two joints, the 



axillary not a syzygy, .... 



2. Cirrus-sockets not entirely obliterated ; post-palmars like 



palmars. 

 (a) Ten to thirty cirri. 



(i.) Ten to twenty cirrus-joints. 

 a. No further division, 



1. parvicirra, Mull., sp. 



2. quadrata, n. sp. 



3. trichoptera, MiilL, sp. 

 japonim, MiilL, sp. 



multifield, MiilL, sp. 

 variabilis, Bell. 



grandicalyx, Carpenter. 



alternans, Carpenter. 



briareus, Bell, sp. 



4. divaricata, n. sp. 

 magnifica, Carpenter, MS. 



5. belli, n. sp. 



6. duplex, n. sp. 



7. nobilis, n. sp. 



1. parvicirra, Mull., sp. 



3. trichoptera, MiilL, sp. 



japonica, Mull., sp. 

 robustipinna, Carpenter. 



8. littoralis, n. sp. 



1. parvicirra, MiilL, sp. 



