CRINOIDEA. 
With the exception of a patina and a brachial, both from Cserhät (Leitnerhof), 
the crinoid remains collected consist of over nine thousand stem-fragments, under 
vvhich term cirri are included. The correct determination of these fossils is a matter 
of no small difficulty; and this is due first to the nature of the objects themselves, 
and secondly to the inadequacy of most descriptions hitherto published. 
The difficulties connected with the nature of the objects themselves spring 
from two causes: first, the relatively slight specialisation of stem-structures among 
Triassic crinoids, and the consequent similarity of the columnals in species, or even 
genera, that otherwise are quite distinct; secondly, the variability of the columnals 
in a single species, or perhaps it would be more accurate to say, the differences 
between the different regions of a stem in the same individual. 
The inadequacy of most of the previous descriptions consists, largely, in the 
absence of detailed measurements, in the small scale of the figures, if indeed figures 
are given at all, and in a general failure to recognise, or at least to mention, definite 
features that might otherwise have afforded material for subsequent diagnoses. There 
is no doubt an inclination to regard the discrimination of species by stem-characters 
as an almost impossible task, for the reasons given in the preceding paragraph; and 
it must be confessed that the study of stem-fragments is not inviting. But, since the 
majority of crinoid remains alvvays will be portions of stems, and since these are in 
fact among the commonest of fossils, it is as well that some attempt should be 
made to discriminate between them, and so to give a fresh weapon to the stratigraphist 
and palaeogeographer. That which P. de Loriol has done for the Jurassic Crinoidea 
of France should be extended to other ages and other countries. 
It is fairly easy to separate the present material into the two old divisions: 
wheel-stones ( Trochitae, which in combination form Entrochi ) and star-stones ( Penta- 
crini of Agricola, Asteriae of XVIII Century writers). In their further study of 
such fragments, and especially of the former, geologists seem to have been guided 
to generic appellations, rather by the ages of the various beds in which they have 
found them than by any structural peculiarities. Thus, Ordovician Trochitae are 
referred to Glyptocrinus, Carboniferous to Actinocrinus, Triassic to Encrinus, and 
Jurassic to Apiocrinus. In a vague way this procedure finds logical justification in 
the principle : Entia non sunt multiplicanda praeter necessitatem. Accepting this, we 
must recognise the existence in Triassic rocks of the following genera: Encrinus, 
