108 Proceedings of the Royal Society of Victorict. 



Helicocpinus plumosus, sp. nov. (PI. XVII. and XVIIL, 



Figs. 1-5). 



Specific characters. — Dorsal cup small^ measuring 6 mm. in 

 greatest width. Tegmen lofty, 13 mm. in lieight, covered by 

 numerous pentagonal plates. With five arms, each branchings 

 once; length of longest arm, 43 mm. Pinnules long and slender, 

 alternating from each side of arm, one to each secundibrach; the 

 latter are slightly longer than broad, and the articulating surfaces 

 are oblique, set on in a zigzag manner. Width of secundibrachs 

 at their base 1 mm. Column pentagonal, with alternating ridges- 

 and depressions. The ridges are very pronounced at and just 

 above the proximal coiled end of the stem ; usually crenelate, with 

 the intermediate area of the columnals finely and transversely 

 striate. Length of column, not including the coiled portion,, 

 88 mm. Greatest width of columnals, 1.5 mm. Proximal end 

 of column coiled in two turns. 



In the arrangement of the pinnules this form resembles 

 Hapalocrinus victoriae, which was described by Dr. Bather, in 

 1897, from the Silurian of Melbourne.^ A crinoid with a 

 similarly coiled column is seen in Jaekel's Acanthocrinus rex.^ 



Occurretice. — This beautiful and singularly perfect specimen 

 occurs in a fine sandy matrix, which seems to have been well 

 adapted for preserving such a delicate specimen. The upper 

 part of the crown of the fossil is represented in relief, but of 

 the stem and the larger part of the calyx only a hollow cast 

 remains. [384-5]. 



■Locality and Horizon. — From a quarry at West Brunswick,, 

 between Albert and Victoria Streets. Silurian. 



Family Decadocrinidae, Bather. 



Genus Botryocrinus, Angelin. 



Botpyocpinus longibrachiatus, sp. nov. (PI. XVIII., 



Figs. 6-8). 



Specific characters. — Cup dicyclic, subtrigonal. Inf rabasals, 5, 

 pentagonal; basals, 5, hexagonal; radials 5, shield shape. 



1 Geol. Mag., vol. iv., p. 337, pi. xv. 

 - Op. supra oil., p. 16, pi. i. 



