1879] 4 The Formation of Cape Cod. 489 
done I cannot tell, for the cocoon of eggs seem to be attached to 
the spinneret. On the following morning a broad funnel-shaped 
rim was built around the tube but not yet covered; by the 24th 
she has made a room lightly covered with moss. 
Rev. Dr. McCook kindly furnished cuts of the nest with the 
open funnel. I append his description, which was published in 
the Proceedings of the Academy of Natural Sciences of Phila- 
delphia: “The tube is about seven and one-half inches deep, re- 
sembling an ear-trumpet (Fig. 1), with the mouth upward. It is 
bent at an angle of 60° shortly below the surface; the upper part 
is a silk-lined funnel that widens outwardly to the margin which 
at the highest point is one and one-eighth inches above the sur- 
face of the ground. The silken lining extends but a little way 
below the surface. The projecting funnel is composed of blades 
of grass (Fig. 2), which are bent down upcn their stalks from all 
sides, overlaid, and rudely interwoven, making thus a background 
upon which the smooth silken lining is placed. The longest 
diameter of the mouth of the tube (Fig. 1), aù, is one and one half 
inches, the shorter diameter cd, is one and one-quarter inches. 
The diameter of the tunnel below the surface is five-eighths of 
an inch,” 
——:0. 
THE FORMATION OF CAPE COD} 
BY WARREN UPHAM, 
1 huk peninsula of Cape Cod, called by Thoreau the “bended 
“ arm of Massachusetts,” the Elizabeth islands, which are a 
continuation from it to the south-west, and Martha's Vineyard 
and Nantucket on the south, are recent additions to the territory 
of New England. They contain no ledges of solid rock, but are 
made up of the ruins and detritus of ledges which have been 
broken and pulverized. This has been done by. decomposition 
under the influence of frosts and rains, by the excavations of — 
‘A previous description of this region, based on observations made in a hasty 
journey for comparison of its drift deposits with those found in New Hampshire, was 
presented a year ago in the Geological Report of that State, Vol. 111, pp. 300-305. 
Since that time the writer has been over this field more leisurely, spending several 
months in amateur exploration from Cape Cod and Nantucket westward to New Jer- 
sey. This has brought a more correct knowledge of the facts, especially in respect 
to the course, in South-eastern Massachusetts, of the series of hills here called ter- 
minal moraines; as well as some changes in opinions, one of these being in respect 
to the probable height of the sea here when these deposits were accumulated, 
