136 A Botanical Study of the Mite Gall [February, 
the block, for, of course, when the saw goes through a block the 
surfaces on each side of it must be alike), yet in most cases it is 
not very difficult to find a series sufficient for the wainscoting of 
a large room or the top of a long counter which match closely 
enough for all practical purposes. 
While it has been my aim in what has been said of the differ- 
ent varieties mentioned to convey some idea of what they are, it 
is wholly impossible to place their beauty before the reader. No 
agate or jasper is more elegant or attractive. Indeed, in looking 
over slab after slab of the marble I have often been reminded of | 
the close resemblance to agate which the surface before me pre- 
sented. The Wakefield marble is, much of it, very similar to 
agate in brilliancy of polish, delicacy of color and general appear- 
ance, though quite unlike it in hardness and costliness. Nor do 
, we ever see slabs of agate five or six feet wide and eight or ten 
feet long, as are some of the slabs of this marble. 
Ld 
“ry 
oe 
A BOTANICAL STUDY OF THE MITE GALL FOUND 
| ON THE BLACK WALNUT? 
BY LILLIE J. MARTIN. 
Dooa to at least four sciences may do original work on 
Erineum anomalum. Since eggs have been found among 
the hairs on its surface and neither mycelium nor spores occur in 
it, it can no longer be ranked among the fungi, and the entomol- 
ogist alone may study the life-history of its inhabitants. The 
chemist and physicist will certainly have somewhat to do if they 
set out to find the forces which are at work in the production of 
the gall. Nor will the botanist be without employment if he 
trace its anatomy and full development. This paper is a state- 
ment of what was seen in a somewhat superficial botanical exami- 
nation of the gall during the month of July. 
These galls usually occur in the walnut on the under side of 
the main petiole, somewhat below the first set of leaflets, but are 
occasionally found somewhat higher up. One or even seven or 
eight galls may be found on the same petiole (Figs. 1, 2, 3). When 
but one occurs the petiole is shortened and the leaf j is rather 
smaller than the normal leaf; sometimes the petiole is slightly 
1 Read before the Section of Biology of the American Association for the Ad- 
vancement of Science in the Philadelphia meeting, 1884. 
