370 CONTRIBUTIONS TO CANADIAN PALEONTOLOGY. 



obtusely pointed tubercles, one at the midheight of the ray and in the 

 centre of the first costal, and one at the point of bifurcation of the ray 

 and in the centre of the second costal. The first interbrachials are 

 ornamented with a large, prominent, upward pointed tubercle in the cen- 

 tre, with linear ridges radiating from it, and the tegmen with numerous, 

 very small tubercles. 



Basals small, inverted : radials hexagonal, broader than high : first 

 costals quadrangular, also broader than higli : second costals pentangular 

 and much broader than high : distiohals 1x2. A respiratory, slit-like 

 opening on one side only of each arm base, and hence ten in all, each 

 opening linear, well defined, placed close to and parallel with the ambu- 

 lacral furrow. First interbrachials single and very large : second inter- 

 brachials also single, pentagonal Mnd bent abruptly inward at their mid- 

 height. Tegmen composed of rather numerovis large plates, the anal tube 

 subcentral and rising gradually therefrom. 



The foregoing description is based upon three well preserved and near- 

 ly perfect specimens of the calyx, one collected at Bartlett's Mills by the 

 Rev. .J. JV[. Goodwillie in 1882 and pi-esented by him to the Museum of 

 the Survey, and two found quite recently at Thedford by Messrs. Kerna- 

 han and Kearney. The first of these is the specimen referred to on page 

 98 of the second part of this volume and identified with D. liratus (Hall), 

 on the authority of Mr. Wachsmuth, who thought that it might be a 

 small form of that species, although it has " only 1 x 2 secondary radials." 

 In view of the more detailed and illustrated description of i). Ztra?».s pub- 

 lished by Wachsmuth and Springer, this identification seems to be no long- 

 er tenable, and the three specimens now under ci.msideration more pro- 

 bably represent a small, strongly and very peculiarly sculptured, ten-arm- 

 ed and previously undescribed species, perhaps most nearly allied to D. 

 pulchellus of Miller and Gurley, which, however, has a )'espiratory slit on 

 both sides of each arm base, or twenty slits in all. Dr. S. A. Miller, 

 who has kindly examined one of these specimens, regards it as' quite dis- 

 tinct from D. jyidchsUus, and from any species known to him. 



DOLATOCBINUS. (N. Sp. ) 



A single specimen of the calyx of a large Dolatocrinus which has a 

 different arm formula to either of the two preceding species, and which 

 is therefore presumably distinct from both, was collected at Thedford by 

 the Rev. Hector Currie in 1882. On the authority of Mr. Wachsmuth, 

 who thought that it has four primary arms in each ray, this specimen was 

 identified with D. laniellosus, the Carahocrinus lamellosus of Hall, on 

 page 99 of the second part of this volume. But, in the first volume of 

 their monograph of the American Crinoidea Camerata, published in 1897, 



