_ Systematic Results. _ 261 
Cassian, have been a perpetual source of trouble to systematists. A final solution 
of the difficulty cannot be expected until every known form shall have been found 
in unmistakeable association with a determinable test. Since, however, such disco- 
veries are not likely to be numerous, we have to do the best we can with other 
methods. There are two lines of attack that promise an advance. One is the 
study of the variations due to position on the test or to individual growth, and the 
comparison of large series, with the aid of biometry when possible. These methods 
are discussed on pages 136—188, and a concrete illustration of them is afforded 
by the study of a large series of radioles differing greatly in form, but all referred 
to a single species, Anaulocidaris testudo, and all distinguished fromr those of the 
corresponding, though less complete, series referred to A. Buchi. The second mode 
of attack is the study of thin sections under the microscope, as lately developed 
by Dr. Hesse (1900). The application of this method in combination with the pre- 
ceding, as well as the careful study of type-specimens, has enabled me to formu- 
late conclusions on a rather wider basis of fact than has previously been attempted. 
These studies have led me to investigate many forms of radiole not actually 
known from Bakony, and a few of the results are mentioned in the preceding pages. 
It may therefore be useful to give here a brief synopsis of the species accepted, 
with their chief synonyms. The name Cidaris is used for certain species, merely 
because it nearly always has been used, and it must not be taken to connote 
more than the Cidarid nature of the radiole. 
Anaulocidaris Buchi (Miwnst. in Goupr.) (p. 155) 
Syn. Cidaris remifera Miwst. 
Var. A. Buchi granulata mut. nov. 
Anaulocidaris testudo n. sp. (pp. 94, 140) 
Cidaris alata Ac. (p. 170) 
Syn. C. semicostata Monsv. 
Varr. C. alata typica 
C. alata subalata p’Orp. 
C. alata poculiformis mut. nov. 
Cidaris @ Orbignyiana Kurst. non C. Orbignyana Ac. (p. 171) 
Synn. C. Klipsteini Marcou non Drsor 
C. ampla Drsor 
Cidaris austriaca Dersor (p. 171) 
Syn. C. ovifera Kupst. non Ac. 
Cidaris dorsata Moinst. ex Bronn MS. (p. 178) 
Synn. C. foratus Quensr. 
Radiolus crumena QueEnst. 
Varr. C. dorsata typica 
C. dorsata marginata mut. nov. 
Cidaris scrobiculata Braun in Monst. (p. 183) 
Cidaris fustis LauBeE (p. 184) 
Cidaris decorata Mbwsv. (p. 185) 
Cidaris fasciculata Kutst. (p. 187) 
Syn. C. avena Desor. 
Ges. LX, pp. 378 —384, pls. xv—xix, Nov. 1908, and pp. 385—430, 1909). In so far as our conclusions 
agree, their absolute independence will give them the more weight. 
