REPORT OP THE STATE PALEONTOLOGIST 1901 571 



17 D. sp. nov. 



18 Ketiograptus tentaculatus Hall r 



19 Glossograptus sp. nov. c 



20 Cryptograptus antennarius Hall ccc 



21 Trigonograptus ensiformis Hall cc 



22 Clirnacograptus sp. nov. c 



23 Lingula quebecensis Billings r 



24 Eunoa acoola Clarlw r 

 Continuous with this bed of black shale is a layer of purplish 



gray shale with numerous light blue specks, probably originat- 

 ing from talcose mud pebbles. This layer contained: 



1 Dichograptus sp. (branches) c 



2 Phyllograptus anna Hall c 



3 Diplograptus dentatus Hall cc 



4 D. sp. nov. v 



The aspect of the faunas of these two graptolite beds, which 

 clearly belong to one zone, is totally different from that of the 

 two preceding zones. Not only are all species new, with the ex- 

 ception of Logan ograptus logani, Dichograptus 

 octobrachiatus, Phyllograptus angustifol- 

 ius, Ph. anna and Lingula quebecensis, and 

 the prevailing genera different, but even the subclass of the 

 Axonolipa, which hitherto alone held the field, has almost en- 

 tirely been replaced by the family Diplograptidae of the Axono- 

 phora. The latter are represented by the genera Diplograptus, 

 Clirnacograptus, Glossograptus, Cryptograptus, Trigonograptus, 

 and Ketiograptus. 



A peculiar feature of this fauna is the sudden outburst of 

 the Dendroidea with a Dendrograptus, four species, in numer- 

 ous individuals, of Dictyonema (two of these of the rare sub- 

 genus Desmograptus), two Callograptus and a Ptilograptus. 

 This subclass however, though reaching its acme already in 

 Cambric beds, reappears, as is well known, with great force in 

 the Magaran and extends even into the Hamilton formation. 

 As only the species of Callograptus and of Ptilograptus, one 

 of each genus, are recorded from the Canadian exposure of this 

 zone, the greater number of species and the profusion of speci- 



