56 The Ottawa Naturalist. [Aug. -Sept. 



whose exact locality is known have been found in the Cystid 

 beds of the Prasopora zone, and about 180 feet below the top 

 of the Trenton. Beside Peterboro and Ottawa, a specimen 

 has been listed by Dr. Ami from Pakenham, Ontario. The speci- 

 mens from Kirkfield identified by Mr. Springer as this species 

 are almost if not entirely all L. rnultihrachiatus . 



LebETODISCUS LORIFORMIS SP. NOV. 



(Plate 1, fig. 6). 



This specimen has long been known to the collectors about 

 Ottawa as one of the prizes of Dr. Van Cortlandt's collection. 

 (Now in the Museum of the Geological Survey, No. 1414). It 

 has always been considered as an abnormal, long-rayed specimen 

 of Agelacrinites dicksoni, and there can be no doubt that it is 

 very closely related to that species, but since it forms one of 

 the "connecting links" with the species of the later formations, 

 I propose to give it a new name. It may be described briefly 

 as a Lebetodiscus with rays so long that each one nearly touches 

 its neighbor, all rays contra-solar, and equally spaced, the outer 

 border of small plates narrow, supra-oral structure apparently 

 as in L. dicksoni. This species is believed to be ancestral to the 

 very long rayed forms for which Hall erected the genus Strep- 

 taster. 



The holotype is 23 mm. in greatest diameter, and is from the 

 Trenton at Ottawa, Ontario. Probably froni the "Cystid 

 beds," about 180 feet below the top of the formation. It is No. 

 1414 in the Victoria Memorial Museum. 



Lebetodiscus billingsi (Chapman). 



Agelacrimis billingsi Chapman, Canadian Journal, 5, 1860, 

 pp. 358, 204. 



Hemicystites (Agelacrinites) billingsi Sladen, Quart. Jour. 

 Geol. Soc. London, 35, 1879, p. 750. 



Agelacrinites billingsi Chapman, Ann. Mag. Nat. Hist, 

 third ser. 6, 1860, p. 157, fig. ; Billings, Canadian Journal, 

 n. s. 6, 1861, p. 516, fig. 86; Chapman, ibid., n. s. 8, 1863, p. 

 199, fig. 180; Expos. Min. Geol. Canada, 1864, p. 110, fig. 86, 

 p. 171, fig. 180. 



Hemicystites billingsi Ja?kel, Stammes. Pelmat. 1, 1899, p. 

 49. 



Local collectors have for a long time recognized two forms of 

 Agelacrinites billingsi in Ontario, one with straight, and one 

 with curved rays. 



Chapman's original specimen, collected at Peterboro, was 

 of the straight-rayed variety. The species has never been 

 properly described or figured, though fairly common. I am 



