1906] The Species of Botryocrinus. ioi 



this figure, that species is B. polyxo. Dr. Weller may reasonably 

 be asked for an explanation.* 



Botryocrinus crassus. 



Homocrinns crassus, Whiteaves, 1889, Con/rib. Canad. Pal. 1, p. 95, 

 Botryocrinus crassus, Bather, 1893, 'Crin Gotland'. Svensk. Vet.-Akad. 



Handl., XXV, No. 2, p. ro3. 

 Botryocrinus crassus, Whiteaves, 1898, Contrib. Canad. Pal. I, p. 375. 



Dorsal cup bell-shaped, inflated near base and slightly con" 

 stricted near middle of BB. RR very slightly projecting towards 

 the facet. Height of cup (14 mm), 100 ; width at base, 32 ; 

 width at summit, 95. IBB wider than high BB 

 higher than wide. RR wider than high below, but less wide than 

 high above. Arm-facet about .66 of R. x supports at least 3 

 tube-plates. Proximal columnal circular. 



Middle Devonian, Hamilton Group, Thedford, Ont. 



Holotype in Mus. Geol. Surv. Canada at Ottawa. Plasto- 

 type in British Museum, No. E 14060. 



Redescription of the holotype (following the order of Dr. 

 Whiteaves' original description): 



Dorsal cup somewhat bell-shaped, rather broad and sharply 

 inflated near the base, and very slightly constricted just about the 

 middle of the basals. Height of dorsal cup, from lower margin 

 of infrabasals to top of radial facet, 14 mm., to bottom of facet, 

 12.75 torn.; maximum width ot cup, 134 mm.; width at base, 4.5 

 mm. Infrabasals (IBB) pentagonal, about one half the size of the 

 basals, and wider than high. Basals (BB) moderately large, 

 about equal in size to the anterior radials ; higher than wide ; the 

 three anterior ones hexagonal, the two posterior ones heptagonal 

 and truncated above. Radianal plate (RA) equal in size to the 

 IBB, rhomboid (see measurements below) and resting obliquely 

 between the two posterior BB, the right posterior radial, and the 

 superior anal plate x. Radials (RR) pentagonal, outer surface 

 nearly flat below, slightly raised in the middle, and above this 



*Dr. Weller has been so generous with his help to me in the past, that on 

 6th Jan., 1806, I presumed to ask for the loan of material that would enable 

 these doubts to be set at rest. Either my letter or his reply must have gone 

 astray, and the publication of these remarks can no longer be delayed. ioth 

 July, 1906. 



