316 



from that locality, described by E. Billings in the first volume of 'Palseozoic 

 Fossils.' " 



B. 2. From the Trenton limestone op Quebec and Ontario. 

 Steganoblastvjs Ottawaensis, Whiteaves 



Astrocystites OUawaensis, Whiteaves 1897. Canad. Rec. Sci., vol. VII, p. 287, 



with the text figures here reproduced. 



Steganoblastus Ottawaensis (Inadvertently 

 written Canadensis), Whiteaves 1898. Idem, p. 395. 



Steganoblastus Ottawaensis, Bather 1900. Treatise on Zoolopry, edited by E. 



Ray Lankester. Part III, The Eohin- 

 oderraa, pp. 209 and 210, figs, vii, 1 and 2. 



The following is a copy of the original figures and description of 

 Astrocystites, from the " Canadian Record of Science" for January, 1897, 

 published in July of that year, but with the numbers of the figures altered 

 to suit this publication. 



Astrocystites Ottawaensis. 



Fig. 21. Fig. 21a. Fig. 22. 



I'igs. 21, 21a, and 22. Astrocystites Ottawaensis. Fig. 21. " Side view of 

 a nearly perfect specimen, shewing the small plates surrounding and 

 perhaps covering the anus, on the left side of one of the ambulacra! areas, 

 at A, and the peculiar sculpture of part of the calyx, natural size." Fig. 

 21a. "Summit view of the same specimen, also of the natural size." 

 Fig. 22. " Radial plate on the left of the anal region of another specimen, 

 twice the natural size, to shew the peculiar shape and sculpture of this 

 plate, also the overlap by the distal portion of one of the ambulacral areas 

 above, and the modification of the upper margin of the plate on the anal 

 side : A— relative position of the anus. " 



" Body or ' crown ' of the organism globose, almost spherical but nar- 

 rowing rapidly below into a very short, slender column or stem, and 

 somewhat five-sided as seen from above. 



" Calyx or dorsal cup broadly conical and entire below the midheight, 

 but divided above into five large, pointed and slightly incurved, sepaloid 

 lobes, with rather oblique and slightly convex sides, by the decurrent por- 

 tions of thfe ambulacral areas. The greater part of one of these lobes, as 

 seen at A," in fig. 21, "is occupied with a cluster of minute plates which 

 surround and either partially or wholly cover the anal opening. 



