WHITEAVES.] FOSSILS OP HAillLTON FORMATION OF ONTARIO. 103 



upwards. Above the bulb the surface is minutely and longitudinally 

 coiTUgated, but near the apex it becomes nearly smooth. 



A certain general resemblance which this spine bears to the spines 

 on the dome of Dorycrinus cornigerus and B. Gouldii, espeeiallj- in the 

 structure of the base, suggests the idea that it may have formed part 

 of the dome of a crinoid belonging to the family Actinocrinidce. 



Ollacrixis spimgerus, Hall. 

 Plate 13, figs. 4, 4a and 4b. 



Tremntocrinv.i apiaigu-ijn, Hall. 1862. Fifteenth Kep. N. York St. ( 'ab. Nut. Hist., 



p. 12S. 

 GunirisUroidocrhius ^piniijcru.v, Meek l^ Worthen. 1866. Geol. Surv. Illinois, 



voi. 2, p. 222. 

 GoniasUrolilocrinua npinigtrun, S. A Miller. 1877. Cat. Am. Pal- Foss., p. SO. 

 OH'icr!riux spinigerw^, "Wachsmuth lV' Springer. Eev. Palfeocrlnoidea, pt. 2, p. 210. 



Near Thedford. collected by the Eev. Hector Currie in 188.3: one 

 perfect and exquisitely preserved specimen of the calyx, with the 

 dome plates in situ, which he has kindly presented to the museum of 

 the Survey. 



" This beautiful specimen shews splendidly the interradial depres- 

 sions described on page 218, part 2, of the Eevision of the Paltco- 

 crinoidea. It also shows well the ambulacral or arm openings, and the 

 extended arm-like water tubes, which are represented exceptionally in 

 this species, from their base ujj, by two independent appendages : 

 while in all other known species of this genus the tubc^^ in this as in 

 the other interradii, respectively, are suturally connected for :?ome dis- 

 tance, being only divided at their outer ends.'' Wachsmuth. 



Me^sr>. ]\Ieek and Worthen with some doubt and Mr. S. A. -Miller 

 2)0sitively state that this species should be placed in Lyon & Casserlaj-'s 

 genus Goniasteroiilocriiuii, rather than in OUacriiais, Cumbei-land. 

 Zittel, however, in his " Handbucb der Paleontologie," ;is well as 

 Wachsmuth & Springer, in the memoir cited above, take the opposite 

 view of the case. 



Ancthocrinus Bur>iiOsDS, Hall. 



Plate 13, fig. 5. 



Ancyrocrimis hidhosw, E.a\l. 1862. Fifteenth Rep. N. York Stalin Cah. Nat. Hist., 

 p. 118, pi. 1, figs. 25 and 26. 



A perfect but worn specimen of the root and pai-t of the column of a 

 crinoid which is clearly referable to the genus Ancyrocrinus and appa- 



