141 



of that species. Quite recently, however, Mr. R. Ruedemann has pub- 

 lished a paper (in the "American Geologist" for 1896) in which he 

 adduces arguments to prove that the specimen upon which S. angusti- 

 folius was based is not a plant, but a number of imperfect shells of a 

 sessile Conularia (probably C. gracilis, Hall) with thickened margins 

 and a bulbous base, attached to the cast of the interior of another shell 

 (Trocholites). However this may be, an original drawing of the type of 

 T. angustifolius, kindly forwarded by Mr. Ruedemann, shews that there 

 is no real resemblance between that specimen and the fossils from Cat 

 Head. 



Chondrites cupressinus, Whiteaves. 



Plate 17, fig. 1. 

 Chondrites cupressinus, Whiteaves 1896. Canad. Reo. So., vol. VI., p. 388. 



" Thallus frondose, continuous, and consisting of a long, slender and 

 extremely narrow rhachis, with numerous short, crowded and variously- 

 divided lateral ramifications; base of attachment unknown. The rhachis 

 is flat, erect, nearly straight, and scarcely more than half a millimetre in 

 its maximum breadth. The lateral ramifications are linear, pinnately 

 partite, or possibly verticillate, opposite, divergent, and spreading out- 

 ward and a little upward. They decrease very gradually in length from 

 below upward, and are either doubly bifurcate, bifurcate with both of 

 the ultimate ramifications trifurcate, or bifurcate with one of the ulti- 

 mate branchlets trifurcate and the other single. 



Oat Head, Lake Winnipeg, D. B. Dowling and L. M. Lambe, 1 890 : 

 one specimen, which has been split longitudinally down the centre into 

 two pieces of nearly equal size. 



To the naked eye this specimen has much the appearance of the poly- 

 pary of a recent hydroid, and especially of that of the well known 

 Sertularia cupressina, L., which Professor Allman now refers to Thui- 

 a/ria. When viewed under an ordinary simple lens, however, it has 

 obviously more the aspect of a plant, although its minute tissues are not 

 preserved. There are no indications of any corneous or chitinpus struc- 

 tures, of articulations, of a central virgula, as in the Graptolitidse, or of 

 marginal hydrotheca, as in the hydroids and graptolites." 



Chondrites gracillimus, Whiteaves. 



Plate 17, fig. 2. 



Chondrites graeilUmus, Whiteaves 1896. Canad. Rec. Sc, vol. VI., p. 389. 



" Thallus frondose, continuous, pinnately partite, with a slender 

 rhachis, which is nearly a millimetre in breadth about the mid-height, 



