7 



Echinodermata 



Glyptocrinus sp. — A portion of a column, apparently referable to this genus, 

 was collected by Joseph Townsend at Streetsville, and is now in the possession 

 of the University. Similar columnals are not uncommon in the Humber member 

 in the quarry at Port Credit. 



Lichenocrinus sp. — Stems possibly referable to this genus are found in the 

 Humber member in the quarry at Port Credit. 



Bryozoa 



Amplexopora solitaria, sp. nov. — See page 17. 



Atactopora sp. — A single example of a thin, frondescent, unilaminar bryozoan 

 with elevated, sub-solid monticules was found in the Erindale member. It is 

 herein referred to the genus Atactopora, but it is not sufficiently well preserved 

 to admit of specific identification. In the spacing of the monticules, it appears 

 to differ from other members of the genus from the Cincinnatian series. See 

 Plate V, Figure 10. 



Atactoporella densa, sp. nov. — See page 18. 



Arthropora shafferi (Meek). — A single example of this species was found 

 among the collections of the Royal Ontario Museum of Paleontology, labelled 

 ''Richmond, Credit River". It probably came from the Erindale member, 

 since it is on the same piece of rock as a specimen of Hallopora aequalis, a new 

 species from this member. It is identical in form and structure with the specimen 

 described and figured by Parks and Dyer from the Humber River section. 



Batostoma cf. varians (James). — A small fragment of a bryozoan was found 

 in the Bythopora meeki zone of the Streetsville member, which is herein referred 

 to the genus Batostoma. The character of its growth could not be ascertained, 

 but the vertical section prepared from it seems to show that its relationships 

 are with the species B. varians of the Waynesville rather than with B. variabile 

 of the Liberty and Whitewater. 



Bythopora meeki, James. — This species is comparatively abundant in the 

 uppermost five feet of strata of the Streetsville member (zone of Bythopora 

 meeki). The following remarks in reference to it are made by Bassler. 1 



The various species of Bythopora are so much alike in internal structure that it is not strange 

 that Nicholson considered the species under discussion only a variety of his Monticulipora gracilis. 

 However, the fact that it occupies and is characteristic of a different geological horizon and always 

 forms a considerably larger zoarium seems to me reason enough for its rank as a distinct species. 



Bythopora gracilis forms long, slender stems seldom over three millimetres in diameter and 

 characterizes the Fairview and McMillan formations while the branches of Bythopora meeki 

 are seldom less than six or seven millimetres in diameter and occur only in the Waynesville. 



The forms from the Streetsville member vary in diameter from one and a 

 half to six millimetres, the average being four millimetres. Thus, in size, they 

 are intermediate between the two species mentioned above. They are referred 

 in this paper to B. meeki on account of their occurrence in rocks which are even 

 higher stratigraphically than those of the Waynesville. See Plate V, Figures 

 4 and 5. 



Calloporella vacua, sp. nov. — See page 19. 

 ^roc. U.S. Nat. Mus., 30, 1906, p. 21. 



