DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 



61 





^v^'^^ 



V 



Fig. 84. — AcANTHOGR,\rTu.s chaetoph- 

 orcs, xew species. holotyfk. 

 (See also Pl. 3, fig. 5.) 



ACANTHOGRAPTUS CHAETOPHORUS Gurley. new species. 



Plate 3. figure 5. 



Gurley 's description is as follows: 



Polypary consisting of several main stems which may rench a thickness of 

 0.4 mm. ; but principally characterized „ 



by very numerous, excessively fine, hair- 

 like, more or less tufted fibers which 

 fringe the sides of the stems and (?) also 

 arise freely from the (invisible) base. 

 Thecje appear to be present, but are in- 

 distinct. 



This species unquestionably finds its 

 nearest affinity in Acanthograptus. It can 

 hardly be a Dendrograpttis, if that term 

 be limited to forms taking origin from a 

 single stem, as the form renders it very 

 probable that it grew in tufts from a 

 transversely extended base. 



Horizon and locality. — Niagara dolomite, Hamilton, Ontario. 

 Holotype. — New York State collection. 



ACANTHOGRAPTUS MULTISPINUS Gurley, new species. 



The description by Gurley is as follows: 



Polypary flabellate-compressed, originating in and sessile upon a black, car- 

 bonaceous, discoid base, from which the main branches arise, and then divide 



and subdivide, run outward, spreading some- 

 what to both sides and being somewhat undu- 

 late; 0.3-0.4 mm. wide; set about 25-30 in 25 

 mm. of width ; their sides beset with processes 

 of variable length and closeness. These pi'oc- 

 esses are in character intermediate between 

 those of A icalkcii and those of A. pulcher, 

 being stouter, more rigid, and more distant 

 than in the latter species, but less stout, less 

 rigid, and closer together than in A. walkcri. 

 Their lengths and closeness are too variable to 

 be well reduced to measurements. 

 The present species most nearly resembles A. pulcher, but in genei'al has the 

 branches more divergent, and with less tendency to parallelism ; the fringing 

 processes are stouter, more rigid, and more distinct, and the resulting appear- 

 ance is less finely feathery. 



Horizon and locality. — Niagara chert, Hamilton, Ontario. 

 Cotypes.—Csit. No. 55309. U.S.N.M., and New York State collec- 

 tion. 



Figs. 85, 86. — Acanthogeaptus 

 multispinus^ new species. 



Two TYPE-SPECIMENS. (FiG. 



85 BY R. S. Bassler.) 



