16 



the Dundas formation on the Credit river. The type of the species was 

 obtained in the Dundas formation on the Humber river. 



Whitella cf. torontonensis, Stewart. — One of the specimens of Whitella 

 from the Humber member at Port Credit is more quadrate in form than the 

 specimens referred to W. hindi and more closely resembles W. torontonensis. 

 This latter species was founded on a single specimen, which was thought' to have 

 come from the Don River valley. 



Gastropoda 



Bellerophon cf. mohri, Miller. — A single specimen of a gastropod closely 

 related in form to this species was found in the zone of Ischyrodonta miseneri in 

 the Streetsville member of the Richmond formation. The character of the 

 mouth, whether widely flaring as in B. mohri, or relatively narrow as in B. 

 sub angular is , Ulrich, can not be determined; but in general proportions and 

 in the smooth character of the surface, the Streetsville specimen more closely 

 resembles the former species. According to Shideler, both of these forms are 

 found in the Saluda and Upper Whitewater in the Ohio valley. 1 



Clathrospira cf. subconica, Hall. — Two specimens in the older collections 

 of the Royal Ontario Museum of ' Paleontology are referred to this species. 

 One was labelled as coming from "Credit river" and the other from "Streetsville". 



Cyclonema sp. — A few body whorls of a gastropod showing the characteristic 

 surface markings of the genus Cyclonema were found in the Columnaria reef 

 of the Meadowvale member of the Richmond on the Credit river. 



Cyrtolites ornatus, Conrad. — This species occurs in the strata overlying the 

 Columnaria reef of the Meadowvale member of the Richmond. 



Liospira helena (Billings). — This species occurs in the Columnaria reef 

 on the Meadowvale member on the Credit river. It is an Anticosti species, 

 but has been reported from rocks correlated with the Whitewater on Manitoulin 

 island. 



Lophospira bowdeni, Safford. — This is the most abundant gastropod in the 

 Richmond of the Credit river, being found in all three members. It is a long- 

 ranging form and, therefore, is of little use in determining the sequence of the 

 rocks. 



Lophospira tropidophora, Meek. — This is another common gastropod in the 

 Richmond of the Credit river. In the Ohio valley, it ranges from the Eden to 

 the Richmond, but in Ontario it is more common in the Richmond formation 

 than in the Dundas. 



Oxydiscus sp. — One poorly preserved example of the genus Oxydiscus was 

 found among the older collections of Streetsville fossils at the University. 



Cephalopoda 



Actinoceras crebriseptum (Hall). — A single example of this species was found 

 in the Credit member of the Dundas formation at Erindale. It is a very 

 abundant species in the Humber member of the Dundas formation in the prison 

 quarry at New Toronto; in New York state it occurs in the Pulaski shales. 



^oerste has described a new species from a similar horizon on Manitoulin island as Beller- 

 ophon parksi. It is possible that our specimen belongs to this new species. 



