192 ROYAL SOCIETY OF CANADA 



comparison. It is to the trilobites, therefore, that we look for the com- 

 parative standing of this sub-fauna and its chronological position. 



On examining the confused assemblage of parts of trilobites which 

 the limestone conglomerate and limestone bands free of pebbles contain, 

 we are struck by the prevalence of pygidia with flattened margins and 

 narrow, prominent rachis ; this form of pygidium is associated with 

 heads that have a comparatively small glabella, and the two together are 

 common features of the genus Anomocare. With these are not uncom- 

 monly found head-shields of the genus Dolichometopus, a genus hereto- 

 fore known only in the Cambrian terrane of Sweden, and there charac- 

 terizing the Upper Paradoxides Beds. 



The grouping of the Agnosti, also, is such as to show a progressive 

 change from the assemblage found in the Paradoxides beds, as hitherto 

 shown in this part of America. The section Limbati, which is most pre- 

 valent in the Eteminicus sub-fauna, and is found in diminished numbers 

 in the Abenacus sub-fauna, is absent from these beds at Hastings Cove, 

 or rare. The Longifrontes still maintain a fair proportion in this sub- 

 fauna, but the Agnosti, which are found in the greatest numbers, are the 

 Parvifrontes, and the most abundant form of this section is (A. umbo) ihe 

 one with the shortest glabella. Here the modification of form has not 

 stopped, as in this sub-fauna we meet for the first time (as far as the St. 

 John Group is concerned) the highly modified section of L^evigati ; A- 

 lœvigatus is occasionally found, a species in which the glabella is almost 

 entirely effaced. The types of trilobites above described, viz., Anomo- 

 care, Dolichometopus and the Lawigate Agnosti are, in Sweden, peculiar 

 to the Upper Paradoxides beds. 



If we consider the species, the connection with the upper part of the 

 Lower Cambrian (Paradoxides beds) is equally close. Of Agnosti there 

 are five Old- World species of the middle and upper Paradoxides beds. Of 

 Microdiscus, one species of the middle Paradoxides beds. Of Agraulos, 

 two of the species belong to the same part of the Cambrian system. 

 Conocoryphe might, as a genus, be considered to mark specially the 

 Lower Paradoxides beds ; but the species from Hastings Cove is unique in 

 its minute size and strongly tuberculated surface. The Paradoxides is 

 P. Abenacus, the American representative of P. Tessmi, which ranges 

 from the middle to the highest Paradoxides beds. Of Dolichometopus we 

 have already spoken. Of Anomocare, though we have not recognized 

 the two typical species described by Angelin, those which arc present are 

 quite as well characterized as the Chinese species described by Dames, 



Though the sub-fauna at Hastings Cove contains a larger percentage 

 of forms of the Abenacus sub-fauna, this is to be ascribed to the fact 

 that the two sub-faunas flourished in closely contiguous basins, and are 

 separated by no great period of geological time. And, further, there is 

 nothing to indicate that any great physical disturbance expelled the 



