HUDSON RIVER BEDS NEAR ALBANY 541 



O. parvus, Hall, co 



<j. sp. n} 



Dawsoni campanulata, Nicholson, c 



Leptobolus walcotti sp. n. r 



Station 30. North end of Lansingburg 



An exceptionally good opportunity for collecting was offered 

 for a time by a large excavation made around the new long dis- 

 tance telephone power-house at the north end of Lansingburg, 

 north of Troy. The rock consists of black, fissile argillaceoua 

 «hales, black, hard, compact argillite and intercalated, green ar- 

 gillaceous shales. The black shale furnished: 



Corynoides calicularis, Nicholson. In immense number 



Didiymograptus serratulus, Hall, rr 



Dioranograptus ramosus, Hall, r 



Diplograptus angustifolius, Hall. Completely covering some 

 surfaces 



D'. aff. putillus, Hall, rr 



D. foliaceus, Murchison. sp. c 



D. whitfieldi, Hall, c 



Ollmaicograptus bicornis, Hall, c 



O. scharenbergi, Lapworth. c 



C. sp. n. cc 1 



O. sp. n. c 



The faunas of Lansingburg and Mt Olympus, which lie in the 

 «ame strike and evidently belong together, differ in general as- 

 pect from that of the lower Dicellograptus fauna by the scarcity 

 of branching forms and the strong prevalence, in species and 

 individuals, of the biserrate graptolites, notably of the genera 

 Diplograptus and Olimacograptus. They ap- 

 proach in this regard the fauna of the upper Dicellograptus 

 beds, to which they could be referred, were it not for the occur- 

 rence of a few stipes of Didymograptus tenuis, 



^The new species of graptolites will be described in a separate, later 

 paper. 



