\'I. liotri/i criiiKs t^'iiintjiiclohus. 191 



RR f), of normal slin))0 ; jiiojectiiii,^ very sliglitlv towanl.s 

 the faeef, le.ss in No. 2. Measmeiiieiits are : — 



Surface of facet not seen. Tlie radial.s bend inwards very 

 sliglitly on either side of the facet. 

 Arms. — In No. 1 : — 



I Br number G and 8. They taper towards the primaxil. 

 Measurements of I Bri — 3 millim. high and oo millim. wide. 

 ]\Ieasurements of lax — 4 millim. high. 3'3 millim. wide 

 below, and 4*6 millim. greatest width. 



From the primaxil s[)ring two rather massive irregular arms, 

 of rather less width than the primibrachs, bearing small 

 armlets at intervals of one, two, or three ossicles. This gives 

 the main arms a slightly irregular appearance, but by no 

 means so irregular as in B. ramosus. About 23 brachials of 

 what we may call the distichal series are visible, and the 

 total length of arm observed is 51 millim. The armlets are 

 very small, the width of the first being 1 millim., or about i 

 the width of the main arm at the point where it originates. 

 Thus they approach the pinnules of B. decadactylus^ but differ 

 from them in their irregular distribution and in the fact that 

 they apparently branch again. 

 In No. 2 :— 



I Br number 5 and 3 and 5 (?), Measurements of I Brj 

 are — 1*9 millim. high and 3 millim. wide. Measurements of 

 I ax are — 2'25 millim. high, 2 millim. wide below, and 2"5 

 greatest width. 



The distichal series are as in No. 1, but the distal part of 

 the arms is lost. At the level where the arms are 1*8 millim. 

 wide, the armlets that spring from them have a width of '8 

 millim. 



Covering-plates, ventral groove, and axial canal are all 

 unseen. 



The Stem in No. 1 is preserved to a length of 49 millim., 

 but there are indications in the matrix of at least 20 millim. 

 more. The mean widtli of the stem, allowing for compres- 

 sion, is 4*2 millim., while the lumen, which is pentagonal, 

 has a width of "75 millim. In section the stem is quinque- 

 lobate, as seen in the outline beside it in the figure. The 

 lobes are interradial in position. The ossicles are of three 

 sizes : large and projecting ; small and less projecting ; small 



14*' 



