Great Oolite near Basle. Bi 
small size of its constituents. The Gastropods are rarely 
more than 1 centimetre in length, and Terebratula mazillata 
averages 3 millimetres. These fossils are true dwarfs, not 
merely young forms; the stunting of growth is accompanied 
by no other change of character. It is, however, noticeable 
that the dwarfs are confined to the lenticular fossil masses ; 
the same species when found, as a few of them are, in the 
freestone courses are of normal size. Some species are con- 
fined to the freestone and are never found as dwarfs. 
The difficulty of figuring these minute fossils was overcome 
by M. Greppin in an ingenious manner, which he was good 
enough to explain tome. A fossil was fixed between wire 
points in the field of a microscope and its shadow thrown by 
a strong light on to a piece of ground glass. On this the 
outline was traced by a pencil. The object was then ex- 
amined by reflected light in the usual way, and the details 
filled in on the glass ; any error can be rectified in a moment 
on this surface. When the glass was filled with drawings it 
was photographed and phototype plates then made. This 
method combines accuracy, clearness, and softness, with the 
great advantage of the author being his own artist. 
The Crinoid stem-fragments, to which [I would now direct 
attention, are found by hundreds at both Muttenz and Buben- 
dorf, and are often slightly worn. They share the stunted 
character of the other fossils, and appear to be the dwarf 
varieties of two species. 
Of these species one is already known as Pentacrinus 
Nicolett, Desor. The greatest diameter of the stem in the 
present specimens (5 millim.) is, however, less than the 
smallest diameter yet recorded for P. Nicolet’, and the 
majority of the fragments have a diameter of only 3 or 4 
millimetres. I have therefore suggested that they should be 
known as P. Nicoleti, var. minimus (fig. 1, p52). Hxamples 
of this variety, found in the Great Oolite of Neue Welt by Mons. 
J. B. Greppin, were seen by me last year in the Strassburg 
Museum (Hlsass-Lothringen Sammlung). The fragments of 
this species are distinguished by the re-entrant angle of the 
lateral faces, and by the depression of the sutures at the angles, 
from the other fragments found in the lenticular beds of 
Muttenz. 
Of what species this other Pentacrinus is the dwarf I do 
not know. I can find nothing exactly like it among Jurassic 
species, and this, combined with its small size, has induced me to 
designate it Pentacrinus Basilew (from Basilea, BEES) (fig. 2). 
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