VII. Mastigocrinus loreus. 195 



wliich come in the family Decadocriniclse. There are two 

 reasons why this was not done : first, that every one who 

 lias seen this species, including myself", has regarded it as a 

 Cyathocrinus ] second, that, until i\\e, gQnQ,Xii Botryocrinus and 

 Cyathocriniis were understood, the reasons for separating it 

 from the latter genus would hardly have been apj)reeiated. 



Of the genus oidy the one species is as yet known, though 

 it is probable tliat several American sj)ecies will be found to 

 belong to it. The descriptions of genus and species must 

 therefore go togetlier, and a diagnosis of the latter can hardly 

 be given. 



Generic Diagnosis. 



Cup cyathiform, with plates of medium thickness. I BB 5; 

 BB 5 ; BR 5. Arms simple, dichotomous, elongate. NoE,'; 

 ic hexagonal, in line with lili; Ventral Sac long, flattened, 

 composed of primitively hexagonal plates which are trans- 

 versely folded. Tegminal plates small, irregular. Stem round, 

 with small pentagonal axial canal, and with radial sutures. 



The appearance of the specimens as they lie on the rock, 

 with their long, wavy, delicate arms outstretched, suggests a 

 knout or cat-o'-nine-tails j hence the name, from fidaTi^, a 

 scoursre. 



The type species is founded on the evidence of five speci- 

 mens, viz. : — 



In the British Museum : 



57048, a magnificently preserved crown, with 36 millim. of 

 stem, seen from the posterior. Matrix a blue shale. 

 Dudley. From the collection of Mr. John Gray of 

 Hagley. (PI. XII. fig. 3, and zincotype, figs. 3-8, 

 and fig. 9 on p. 198.) 



In the Museum of Mason College, Birmingham : 



133, a fairly complete crown, with 24 millim. of stem; seen 

 from left side ; rather disturbed and overgrown by 

 Polyzoa. Matrix a rough limestone. Dudley. 

 (PI. XII. fig. 2.) 



In the Museum of the Dudley Geological Society : 



(a), a portion of a crown, with traces of ventral sac and 66 



millim. of stem ; seen from anterior. Matrix a blue 



shale. Dudley. (P. 200, fig. 10.) 

 {b), a smaller crown broken distally, with 8 millim. of stem, 



seen from posterior. Matrix a blue shale. Dudley. 



(PI. XII. fig. 1, and zincotype, fig. 1.) 



