170 BULLETIN OF THE 



portions of the cirri, as is markedly the case in P. decorus, and less so in P. miil- 

 hri and in most species of the genus. It has therefore often been said that 

 the nodal joints of P. asteria are simple and low, while those of P. miilleri are 

 double and thick. This is not strictly true. The nodal joints are always single 

 and united by syzygy to those next below them, though the line of junction is 

 frequently almost obliterated. The hypozygals may be modified to receive the 

 cirrus-bases, as in P. miilleri and P. decorus, or they may not differ in external 

 appearance from the other internodal joints, as in P. asteria and P. wycilb:- 

 thomsoni. In this last species, however, the joint above the node is slightly 

 excavated to receive the wide basal portions of the cirri, and this character is 

 still more marked in the genus Metacrinus. 



P. mulleri Oerst. 



Stem generally robust, reaching 6 mm. in diameter, with 4-10 (usually 6-9) 

 internodal joints. The cirrus-sockets, which do not reach the upper edges of the 

 nodal joints, are variable in shape. Some are oval, and encroach but little on the 

 hypozygal, while others are more circular and extend well down on to it. 



Cirri reaching 50 mm. in length and composed of about 40 stout joints. 



Lowest limit of the interarticular pores from the fourth to the eighth npde. 



The two outer radials united by syzygy. There are usually 6 or 8 anus 

 on each ray in the following order, 2, 1 ; 1, 2, or 2, 1, 1 ; 1, 1, 2. the axillaries 

 being limited to the outer arm of each successive pair. Primary arms of 2 

 (distichal) joints, which are united by syzygy. Secondary arms of 2-7 (palmar) 

 joints, usually 3. The two following divisions are usually of 3 joints each, 

 but may have 5 or 6. The first two joints after the palmar and subsequent 

 axillaries are united by syzygy with a pinnule on the epizygal. No other 

 syzygiee on the arms. 



The lower joints of the pinnules are somewhat prismatic, and the following 

 ones laterally compressed, wuth sharp dorsal edges. 



Examples of this type were dredged by the " Blake " at the following 

 stations * : — 



1877-78. Off Havana. 175 fathoms. 

 1878-79. No. 193. Off Martinique. 169 fathoms. 

 No. 291. Off Barbados. 200 fathoms. 



/,'■ marks. — A dry example of this species was obtained by Sir Wyville Thom- 

 son from Mr. Damon, and a spirit one was; brought home from Barbados by 

 Sir Rawson Rawson. Its stem is readily distinguished from that of P. asteria 

 by the shortness of the internodes and the modification of the hyposygal joints, 

 which, however, is far leas marked than in P. deconu. The basala generally 



* The complete list of localities for the different Crinoida dredged by the " Blake " 

 will doubtless be drawn up by Mr. Ag"*"" and bis assistants. I Cannot, of com-.', 

 do more than record the localities of the selected spedmena which have bean --cut to 



Europe for study. 



