SPENCER NIAGARA FOSSILS. 579 



■dition imperfectly unite or overlie each other, producing- a kind of 

 fine net-work with irregular ellipsoid interstices. In texture it is 

 corneous, and has the branches marked with striations of a sub- 

 rhomboidal form. The terminations of the branches are dichoto- 

 mous. 



In this species the branches are finer than in C. cyathiformis 

 (var)ing from 0.35-0.75 of a millimetre in breadth), with more 

 numerous and irregular bifurcations. The small branches over- 

 lie (or are connected with) each other, giving a netted appear- 

 ance, and sometimes there is the resemblance to cross-bars as in 

 Dictyonema ; but from this genus it is easily distinguished by 

 want of a system of cross-bars, and by the very irregular branch- 

 es, and irregular or ellipsoid meshts of the net. The frond is 

 sometimes flattened in a circular (and sometimes in a fan-shaped) 

 form, showing the basal extremity as if attached. My largest spe- 

 cimen is ten centimetres high, and when complete it had as great 

 a breadth near the summit. 



Formation and Locality. — This species is found principally in the 

 shaly dolomites below the "chert-bed" of the Niagara formation 

 at the ''Jolly-cut," Hamilton, Ont. 



Calyptograptus micronematodes, nov. sp. 



Plate X Fig. 4 and Xa. 



Frond cyathiform in its growing state, with numerous lateral 

 branches originating from the older stipes. The branches over- 

 lie each other, and may be united in some cases, but without true 

 cross-bars. The whole frond has an anastomose appearance with 

 irregular rhomboidal interstices. The texture is corneous (though 

 sometimes replaced by pyrites, and the surface is marked with lon- 

 gitudinal striations, which in some places appear to represent the 

 position of a solid central axis. The terminations of the branches 

 end in two or three points. The branches in this species are very 

 delicate, being about a quarter of a millimetre broad, and each 

 branch is not more than from one to two millimetres in length, 

 before it overlaps or touches the adjacent stipe. The greatest 

 diameter of the frond is not more than four centimetres. Only 

 two or three specimens of this beautiful little frond have been 

 obtained. 



Formation and Locality. — I obtained this species, near the base 



