6 



BULLETIN 65, UNITED STATES NATIONAL MUSEUM. 



Nine species of Dendrograptvs are here noted, two of which are 

 new. This is not the complete representation of the genus at Hamil- 

 ton, Ontario, since Doctor Giirley's manuscript includes short descrip- 

 tions, unaccompanied by illustrations, of three additional species, 

 each of which is represented by a single specimen said to be in the 

 New York state collections. As these specimens are inaccessible at the 

 present time the descriptions are omitted. To complete the notes on 

 this fauna, however, it may be added that one of these species is a 

 very slender, rigid little form, with sharp, V-shaped bifurcations; the 

 second has very thick stems and branches, the latter upright, close 



'.♦'?x 





'>>/ 



f*^. 



Figs. 1-7. — 1, Dendkograptus dawsoni Spencer. A feond natural size and a branch 



ENLARGED ; 2, D. DUBIUS MILLER ; 3, D. RAXIOSUS SPENCER. A FROND WITH A BRANCH 



enlarged; 4, D. praegracilis Spencee ; 5, D. spinosds Spencer; 6, D. ? problemat- 

 icus Spencer; 7, D. frondosis Spe.ncer. A frond natural size a.nd branch en- 

 larged. (Copied fro.m Spencer.) 



together, and parallel, while the branches of the third are narrow 

 at their origin, but widen uniformly to their bifurcations or free ends. 



DENDROGRAPTUS DAWSONI Spencer. 



Text figure 1. 



Dendrograptus daicsoni Spencer, Can. Nat., X, 1,S82, p. 105. nomen nufJum; 

 Trans. Acad. Sci. St. Louis, IV, 1884, pp. 564, 568. pi. 1, fig. 5; Bull. 

 Mus. Univ. State Missouri, No. 1, 1884, pp. 14, 18, pi. 1, fig. 5. — Miller, 

 North Amer. Geol. and Pal., 1889, p. 184.— Gurley, Jouru. Geol., IV, 

 1896, pp. 94, 308. 



Doctor Spencer's description is as follows: 



Frond erect and treelike. Stipe short, hut extending upward and dividmg 

 into two or three principal branches, (.'ach bifurcating twice or thrice, and at the 



