88 Correspondence. 
tains.* The green marble is found at various points, in a NW. 
direction, or thereabouts, from this spot; and it apparently forms a 
bed with a ‘strike’ of about NW.—SE.; and it rises in many 
places like a wall above the mica-schist of the country, the latter 
rock having been more easily denuded. The northern end of the 
bed is far more calcareous than the southern, and there the Eozoan 
specimens are very unsatisfactory. As it is many years since I col- 
lected my specimens, these notes of the locality are from memory, and 
may be corrected by later observation. This marble gives way in 
parts to the action of acid (but not so easily as the Canadian marble 
that Sir W. Logan gave me), leaving tubuli like a white velvet coat- 
ing on the cell-masses, and with an occasional thread going right 
across. It seems as if the carbonate of lime has here been replaced 
partly by some other mineral, resisting the acid. Yours very truly, 
W. A. SANFORD. 
NyneHEAD Court, WeLiineton : Dec. 27, 1864. 
Note by the Eprror. 
Mr. W. A. Sanford, F.G.S., first wrote to me on November 25, 
1864, of his finding Eozoal structure in the Connemara marble; 
but he did not then feel certain enough of his conclusions to put 
them in print. When he felt sure, however, of his results, he 
kindly sent me the ‘slides’ above mentioned; and having got some 
pieces of ‘Ivish Green’ from marble-works in London, I verified his 
discovery by experiment. My specimens, however, of the light- 
ereen, translucent, serpentinous marble have yielded much more 
readily to dilute acid than Mr. Sanford’s specimens; and, excepting 
that the silicate replacing the ‘Sarcode’ of the Hozodén is lighter 
than in a specimen with which Sir W. Logan favoured me, there is no 
real difference between the two. The various-formed chambers, the 
shell of varying thickness,—either very thin and traversed with fine 
tubuli, the silicate filling which (when bared) resembles white velvet- 
pile, or thick and traversed with brush-like threads, representing 
the pseudopodian passages of the ‘supplemental shell’ (or ‘ vas- 
cular system ’),—are all present ; though I have not so carefully pre- 
pared them as they are shown in specimens of the Canadian Hozoan 
rock prepared and given me by Dr. Carpenter, whose researches (as 
read before the Geological Society—see Grou. Mac. Vol. II. p. 35) 
have even added to Dr. Dawson’s almost exhaustive description (see 
Grou. Mag. Vol. I. p. 226) of this fossil. The best way, perhaps, 
to examine the rock for Hozo6én is to strike off thin chips of the 
marble, parallel with a smooth face, cut across the wavy white and 
green lamin, as nearly at right angles as practicable (the direction 
in which ornamental slabs of this marble are often cut), and to 
submit the chips to the action of very weak dilute acid (not sul- 
phuric); and the peculiar structure, at first sight merely granular 
(where the mass is more green than white), but showing to the prac- 
* An account of the Geology of the Connemara Mountains, with their beautiful 
green marble, quartz-rock, and mica-schists, illustrated by a section, may be seen 
im _Murchison’s ‘Siluria,’ 2nd edit. p. 100, &c.—EHorr. 
