ECHINOIDEA. 
The Echinoid remains from the Balaton district consist of radioles, of isolated 
plates or larger fragments of test, and of portions of the jaw-apparatus. As in the 
case of similar material from St. Cassian, the different structures do not occur in 
such intimate association that one can be said to belong to the other. It is there- 
fore necessary to treat them quite separately, leaving it for future discoverers to 
associate the radioles and jaw-fragments with their respective tests. The only case 
in which another course might have been more convenient is that of Anaulocidaris 
testudo, for here there is reason to believe that certain interambulacrals were the 
bearers of certain radioles. The evidence, however, is not direct but circumstantial 
and presumptive, so that the conclusion was come to very gradually and may after 
all be wrong. 
Since, so far as these Triassic remains are concerned, it is rarely, if ever, 
possible to be sure of the genus to which a radiole or a jaw-element belongs, a 
better idea of the systematic relations of the fauna will be obtained if the fragments 
of test are taken first. Unfortunately even these are so incomplete, ambulacrals and 
interambulacrals being rarely found in conjunction, that their ascription to established 
genera is frequently subject to much doubt. If I have ventured to name more of 
these small and obscure remains than scientific caution warrants, it has been less 
with the intention of professing an illusory perfection, than in the hope of attracting 
to them the attention of better qualified critics. It would not have been altogether 
blameworthy to pass by the greater number of these fossils as «indeterminable frag- 
ments», and so to save the excessive delay that has resulted from my attempt at 
an exhaustive study. But if material of this kind is to be described at all, the 
description must be minute. Only thus can the work have any value for either 
stratigrapher or zoologist. 
The fragments of test. 
Terminology. — The terminology at present applied to the test, as also to 
the other skeletal elements, of the Echinoidea, has been gradually evolved from the 
days of Aristotle through the writings of many authors, of whom the following are 
hereinafter referred to: 
J. T. Kum, Naturalis dispositio Echinodermatum. Gedani; 1734. 
C. Des Mouuins, Etudes sur les Echinides. Actes Soc. Linn. Bordeaux, VII, pp. 
167—245, 315—432; 1835, and IX, pp. 45—364; 1837. Separately issued, 
pp. 1—820. 
