288 Mr. Brockbank and Mr. C. E. de Range on 



The thin seam of green marl, which underlies the lowest 

 of this group of limestones, is very fossiliferous with 

 minute organisms. Spirorbis shells abound in it, and 

 there are to be seen under the microscope minute and 

 very delicate bivalve shells, detached and often much 

 broken up. The marl is frequently cellular, but the white 

 partings are probably merely calcareous fillings of the 

 spaces round the sandy grains. There are» however, small 

 sponges and Entomostraca ; in fact, the minute fossils 

 here present are similar to those seen under the microscope 

 in sections of the limestones which overlie them. A large 

 quantity of this interesting green marl has been saved for 

 future examination, as it appears likely to yield the 

 organisms which are found in the substance of the 

 limestones. 



Under the green marls come 9 inches of red rubbly 

 rock, deeply stained by hematite, and containing about 10 

 per cent of iron. 



The next measures consist of variegated marls, purple 

 and green, from 5 to 7 feet thick, which are full of plant 

 remains. Coprolitic nodules (fish-eyes) are also abundant. 

 The plant stems vary from J^^in. to an inch in diameter, and 

 are always flattened. A large number have been examined, 

 but they are always filled in with a fine micaceous marl, and 

 no trace of structure can be made out, except the outward 

 bark and the form of the stems. Leaf-like markings occur 

 in plenty, but no distinct leaf forms have been detected. Nut- 

 like objects occur, with the stems and leaves, in abundance, 

 but always filled in with a micaceous matter, without any 

 trace of shell. It has been suggested that these plant- 

 remains represent seaweeds, or water plants, and that the 

 nut-like ovals have been the air vessels. The general 

 appearances are those of seaweeds. A large quantity of 

 this clay with plant-remains has been reserved for future 

 examination. 



