hovey: artesian well at key west. 73 



but an occasional particle of larger size, even up to a millimeter in diameter, 

 occurs. These larger grains are well rounded and somewhat rough on the ex- 

 terior, rendering them less transparent. The quartz particles are recognizable 

 with an ordinary lens. No recognizable fragments of organisms were noted, 

 except a very few of lainellibranch shells. A very little oolitic material was 

 noted. 



275 feet. — Color white. This rock is more compact than' the last, and may 

 be described as a rather solid lime sandstone. (I use this term as meaning a lime 

 rock in which the individual grains of calcareous sand are readily discernible. 

 It would bear somewhat the same relation to compact limestone that ordinary 

 siliceous sandstone does to quartzite.) Some fragments in the sample are of 

 compact limestone. The amount of limpid quartz sand is larger than in the 

 last sample. Recognizable organic remains are very scarce. Noted, however, 

 one or two pieces of coral, a few bits of bryozoa, and a good many more of 

 lamellibranch shells and casts. 



300 feet. — Color white. This is a sand-rock containing some portions of 

 dense limestone and a small percentage of oolite. Very few determinable 

 organic remains were observed. Noted a few bits of millepores, a few frag- 

 ments of bryozoa, coral doubtful, pieces of lamellibranch shells of several 

 genera, and a very few internal casts of minute gastropods. A very noticeable 

 proportion of the limpid quartz sand is present. Some measurements of grains 

 gave diameters of 0.12 mm. and 0.1 mm. as average, with an occasional larger 

 particle, one of which was 0.55 mm. across. The mass of the rock is made up of 

 white calcareous sand cemented together too firmly to be crushed between the 

 fingers. There are a few ovules. These are easily distinguished by their regu- 

 lar form and smooth exterior. A thin section made from a hard lump shows a 

 structure comparable with that of a Palaeozoic Stromatopora. The cells are too 

 irregular to be those of a millepore and the reticulate structure may be due to 

 anchylosed branches of a nullipore. (A similar organism from 500 feet shows 

 that these apparently solid branches are tubes.) 



325 feet. — Color a yellowish gray-white. Limpid quartz sand, as in last 

 three samples. The sample is made up almost wholly of fine, angular cal- 

 careous sand, but there are some lumps. It was a sand-rock. Ovules are 

 scarce but present. Very few fragments are determinable. Some are appar- 

 ently nullipores. Spines and plates of echinoid tests are relatively numerous. 

 Branching bryozoa not rare. Some few bits of lamellibranch shells. Very, 

 very few remains (casts) of gastropods, one of which is a comparatively large 

 trochoid shell. Annelid tubes in groups and singly. Found several (half a 

 dozen or so) foraminifera. The single annelid tubes are strongly curved and 

 may be Spirorbis. 



350 feet. — Color a yellowish gray- white. Small quantity of the quartz 

 sand present. One fragment, at least, seems to show the terminal crystal 

 planes. A few considerable fragments of coral are in the sample, and frag- 

 ments (spines and pieces of test) of echini and lamellibranchs. One piece is 

 apparently part of a group of annelid tubes. No ovules observed. The rock 



