160 BULLETIN: MUSEUM OF COMPARATIVE ZOÖLOGY. 
(2) The matrix of the conglomerate contains a large amount of 
felsite and considerable feldspar in addition to quartz. ‘The grains 
are variable in size and shape and give little appearance of arrange- 
ment. The cement is generally silicious but near outcrops of felsite 
the mass of the conglomerate becomes more felsitic and tends to grade 
into that rock. 
(3) Felsite, quartzite, and granite, in the order named, are the most 
abundant substances among the pebbles. ‘The latter are variable in 
size and shape and are on the whole subangular. Gradations in size 
have been noted north and south of certain zones and generally east- 
ward. Squantum and Huit’s Cove furnish marked exceptions in 
this respect. No glacial markings were found but pressure striations 
and other evidences of deformation were seen. 
(4) In general but little sorting has taken place among the pebbles. 
Materials of many sizes and shapes occur at the same locality. 
(5) Gray and purplish colors predominate among the conglomerates 
but green is also frequent. 
(6) The specimens and slides studied show melaphyr intrusive into 
the conglomerate. 
(7) The finer sediments contain a considerable amount of felsite and 
feldspar but a much smaller proportion than the conglomerate. 
(8) The sandstones and grits are often not well sorted and their 
grains are usually angular or subangular. 
(9) Gray and purple tints predominate in the finer sediments, as 
in the case of the conglomerates. 
(10) The bedding of the sandstones and slates shows at least some 
irregularities. 
(11) In the cases studied melaphyr is intrusive into the finer sedi- 
ments. í 
THE NORFOLK Basin SERIES.— Arkose. In the Norfolk Basin 
the main outcrops of arkose occur at Pondville. The rock resembles 
granite but careful inspection reveals its true clastic character. In 
thin section it is seen to consist mainly of microperthite and quartz 
with the broken edges cemented with fresh quartz. There is some 
chlorite and ferruginous matter but the feldspars are fairly fresh. 
Conglomerate: — Matrix. The chief materials that compose the 
matrix of the conglomerate in the order of their abundance are 
quartz, felsite and feldspar. Other substances of lesser importance 
are argillaceous material, secondary mica, chlorite, and epidote. 
The matrix of the Norfolk Basin Conglomerate differs from that of 
the Roxbury Conglomerate chiefly in the possession of a higher 
