HOVEY: ARTESIAN WELL AT KEY WEST. 75 



the last, and next to nothing is determinable. Small amount of the limpid 

 quartz sand with the usual features. Fragments of a bryozoan and a very few 

 lamellibranchs and echini noted. The sample includes lumps of firin white 

 oolite. 



500 feet. —Color decided gray, with white fossils and pearl-gray limestone. 

 Sand-rock, rather friable but with hard lumps. Contains some fossds, which 

 are white, and some white aggregations, as well as fragments of compact gray 

 limestone. Occasional small lumps of white oolite are present. Quartz sand 

 present in small amount as before. Pieces of compact gray limestone show, in 

 the thin section, the stromatoporoid structure noted at 300 feet and doubtfully 

 referred to a nullipore. This is made up of branching, anchylosed tubes 

 solidified by calcite. Fragments of lamellibranchs, ono of them a Corbula, 

 another an Area (?) ; spines and other parts of echini. A nearly entire spine 

 had been perforated lengthwise by a boring lamellibranch now in it. Bits of 

 coral are not rare. There are also a few fragments of bryozoa. Gastropod 

 remains are very scarce. Saw part of internal cast of one minute one. 



525 feet. ■ — Color decided gray, with white lumps and yellow-white fossils. 

 A very friable sand-rock containing masses of hard white porous rock and white 

 fossils and calcite. Much like preceding in color, amount of quartz sand, etc. 

 It is composed of loosely compacted, very fine calcareous sand, with few solid 

 fragments and almost nothing recognizable. A piece of porous limestone 

 shows moulds of lamellibranch shells, spines of echini, etc. There is also a 

 piece showing the " stromatoporoid " structure, like those in the material from 

 300 feet and 500 feet. Some oolite ; secondary calcite, of course. Some indi- 

 cations of coral. 



550 feet. — Color decided gray, like 475. A very friable sand-rock, very 

 uniform in color and texture. Almost no bits of white. The small amount 

 of quartz sand present is relatively coarse in grain. Eemarkably destitute of 

 determinable fragments, recognized none in fact. 



575 feet — Color decided gray, like 475. A friable sand-rock like the last 

 except that it contains some recognizable fragments. Small amount of the 

 quartz sand present. Some ovules and an occasional small piece of oolite 

 present. Sample mostly a very fine sand, more than two thirds of it going 

 through a No. 40 mesh sieve. Fragments of lamellibranch shells, one minute 

 gastropod, three or four bits of bryozoa, and one piece of coral recognized. A 

 few foraminifera of the genus Amphistegina were noted. 



600 feet. — Color decided gray, like 475, but lighter shade. A friable sand- 

 rock containing much white material which is mostly crystalline limestone or 

 granular calcite. Quartz sand in small amount as before, very fine grained, 

 angular, no large particles. * A few ovules are present and some fragments of 

 lamellibranchs together with the facetted fragments. More than three fourths 

 of the sample went through the sieve, much of the fine stuff being mere dust. 

 Almost nothing determinable. 



625 feet. — Color gray, like 600. A very friable sand-rock, but with less 

 white material in it and therefore darker colored as a whole. Limpid quartz 



