110 TRANSACTIONS OF THE [FeB. 23 



The green sandstone which accompanies the nodules is also 

 met with at Hanford Brook, in the Basal or Etcheminian series 

 of rocks underlying the St. John Group. In Division 16- of 

 the latter it is found as an irregular layer 2" to 4" thick, with 

 fine gray sandstone on one side, and the layer of nodules, 

 followed by a thin seam of fine shale, on the other. Only loose 

 blocks were esjjosed at this point, the bed-rock not being- 

 accessible, and hence the actual position of the layers could 

 not be determined. In Div. Ib^ the green sandstone is found 

 in spots and patches scattered through the lower and middle 

 part, and at the toj) makes an irregular bed averaging some 6" 

 thick as far as exposed ; but there may be considerably more. 

 It is accompanied by hard phosphatic nodules, and with them 

 contains what few fossils are found in this zone. 



The nodules of Ib^ have been mentioned by G. F. Matthew, 

 in connection with others occurring higher up in the series, 

 near the city of Saint John, and have been considered to be 

 probably coprolites, due to some large soft-bodied animal. 



Appearance in Thin Section. — When examined in thin section 

 under the microscope, the nodules of Zone 2 are seen to be 

 composed of an amorphous, flocculent or granular, light brown 

 substance, which, judging, from the analysis of the nodule, is 

 probably a mixed j^hosphate of lime and iron. It is full of 

 fragments of tests of Protozoa, aj^parently of more than one 

 kind ; some look like Foraminifera, others resemble very much 

 the microscopic bodies occurring in supposed sjiionge-rock from 

 Caton's Island on the St. John River, and which have been 

 described* under the name of Monadites. These may be 

 gemmules of sponges. Besides these, there are seen in the 

 sections three-rayed bodies, which may be spicules of lithistid 

 sponges ; and here and there is a section of a much larger test 

 having the outline of a crustacean, and which may generally be 

 referred to Protolenusf , which is almost the only fossil, not 

 microscopic in size, found in this seam. 



The tests are for the most part preserved in calcite, but often 

 also in chalcedonic quartz, and sometimes in a jiale yellow, 

 highly refracting mineral, which shows an aggregate polariza- 

 tion in low colors. This may be a variety of phosphorite. The 

 more perfect tests are, when complete, usually filled with calcite, 

 less often with glauconite or the pale ^^ellow mineral just 

 mentioned. When partly broken, they are generally filled by 



*G. F. Matthew. " On Cambrian Organisms in Acadia," in Trans. Roy. Soc. 

 Canada, Vol. VII.. See. IV., p. U7. 



t A genus created by G. F. Matthew, in Bull. Nat. Hist. Soc. N. B., p. u. to 

 include a number of allied forms of Olenoid trilobites of Lower Cambrian age. 



