234 Mr. J. Hopkinson on a new Dendroid Grajitolite. 



and Dictyonema, in having " a common trunk or stem, or 

 growing in sessile groups of stipes from a common origin, 

 without distinct bilateral arrangement of the parts," and also 

 in having its hjdrothecai ^' in single series on one side of the 

 stipes or branches, and arranged along a common canal or 

 axis," and differs from them in having its branches " unfre- 

 quentlj and irregularly connected bv transverse processes " 

 (Hall). 



CallograpTUS RADICANS has a diffuse flahelliformpolypary^ 

 with an elongated erect and robust hydrocaulus, terminating 

 proximally in a spreading fibrous liydrorliiza. The poljpary, 

 in the only specimen in which this rooting termination or 

 hydrorhiza has been seen, is at least six inches long ; and its 

 extreme width, where the branches terminate distally, appears 

 to have been about the same. The hydrorhiza covers a 

 space about half an inch square, but is very irregular in shape. 

 It appears as a series of interlacing or anastomosing fibres 

 which must have formed a kind of network over the surface to 

 which it adhered. The hydrocaulus or main stem is about 

 1-lOth of an inch inwadth at its junction with the hydrorhiza, 

 increasing to twice this width where the first indication of 

 branching occurs, its length between these two points being 

 exactly one inch. It has a striated surface and an irregu- 

 larly crenate outline. The branches bifurcate frequently 

 and continuously throughout their length, diverging only 

 slightly at first ; but after the first few bifurcations the whole 

 polypary rapidly widens out, and towards its distal extremity 

 the branches frequently diverge from each other at a wide 

 angle. They vary from l-50th to l-30th of an inch in width, 

 but, being much compressed, must have been originally of 

 greater tenuity. They frequently anastomose ; but this, as in 

 G. 8alteri^ Hall, does not appear to be a constant character. 

 Unfortunately the state of preservation in which this species 

 occurs does not allow the form of its hydrothecfe to be di- 

 stinctly made out. Some of the branches show minute oval 

 impressions arranged in a single series along their centre, the 

 longer diameter or major axis of the oval being parallel with 

 the margins of the branches. These impressions, of which 

 there are about twenty to the inch, most probably indicate the 

 apertures of the hydrothecfe. 



This species is very distinct from the two previously de- 

 scribed species of Galhgraptiis. It is much larger and more 

 robust in all its parts than G. elegans, Hall ; and its branches 

 originate from the main stem in a very different manner. To 

 G. Salteri, Hall, it is more nearly allied ; but its branches 

 bifurcate in a more irregular manner than in that species, they 



