REPORT OP THE STATE PALEONTOLOGIST 1902 939 



among the graptolites of the Cambric of the St John basin, is 

 also present and recognizable by its small meshes and closely 

 arranged thecae, 17 of which were counted in the space of 10 

 mm. But it must be added, that all these varieties occur inter- 

 mingled in the same band and are connected by transitions. 



Clonograptus proximatus Matthew. We will not enter here on 

 a description of the development of this species, nor on its 

 interesting structure, but defer that part of the investigation to 

 the description of the fauna. But it is here pertinent to point 

 out that Emmons had evidently this form before him when he 

 described his Staurograptus dichotomus. 1 This 

 species of Emmons has, ever since its publication, been con- 

 sidered with some distrust as a somewhat dubious form; and 

 this with some justification, for Staurograptus is, compared 

 with other graptolites, an odd looking fossil. 



Staurograptus has been recognized again by Lapworth in the 

 Cape Hosier (Quebec) zone [loc. cit. p. 168] and is referred to as 

 the " dubious genus Staurograptus of Emmons." Gurley cites the 

 genus in his list without any comment, evidently because he 

 did not know what to make of the form. Our large material 

 of Clonograptus proximatus, which contains all 

 growth stages from the sicula upward, includes also Emmons's 

 Staurograptus in unmistakable specimens and in great number. 

 The peculiar branching of this form, which produces a cross in 

 the center, instead of the crossbar (funicle) of the other Dicho- 

 graptidae is the surest means of its recognition. Emmons's 

 Staurograptus is but a very early growth stage of C 1 o n o g r . 

 proximatus Matthew. 



Emmons found his specimens in " the black Taconic shales of 

 Rensselaer county, N. Y." 



There occurs in the Clonograptus bed still another species of 

 Clonograptus which is readily distinguished by its very loose 

 branching and the small number of branches. This form is 

 closely related to, if not identical with, Graptolithus 

 mile si Hall. 2 The habit of both species is alike, and the 

 thecae fail to show any differences ; Clonograptus milesi 

 has been found at Schaghticoke, though in much larger speci- 



1 American Geology. 1855. 1 : 10 \ pi. 1, fig. 21. 



2 Geology of Vermont. 1861. ' : 372; v. 2, pi. 13, fig. 2-4. 



