356 Dr. Fowrtaw—Echinid Fuuna of the Neogene. 
in these materials eighty-two definite forms (species, mutations, or 
varieties referable to twenty-three different genera). 
The Holostomata are not numerous; Cvdaris avenionensis, Desm., 
is represented by somewhat numerous radioles and some isolated 
plates; Leiocidaris scille, Wright, by tests and segments. The 
‘‘oangue’? of one of these tests contains some radioles which are 
very different from those attributed by Lambert to this form — 
(J. Lambert, Heh. mioc. Sardaigne, p. 18, pl. i, figs. 11, 12). On 
the other hand, at a higher horizon than that of Z. sev/la, radioles 
are present similar to those figured by Lambert, and which I have 
named ZL. geneffensis. The ZL. sismondai, Mayer, is represented by 
a unique specimen from the point of view of its preservation, an 
entire test in no way deformed by compression having been obtained 
by Dr. Hume in the Inner Zeit Valley, also by fragments of tests of 
some size and fairly numerous radioles. 
The Glyphostomata belong for the most part to the Echinine. 
The Psammechinus are numerous, eight different forms, some of which 
give evidence of indisputable passages to the sub-genera Anapesus, 
Holmes, and Schizechinus, Pomel; thus showing the little value to be 
attached to these determinations, of which the utility never seemed 
clearly demonstrated. In close relations to the Psammechinus are a 
number of small sea-urchins, to which certain authors, who ascribe an 
exaggerated importance to the very difficult study of the pedicellariz, 
which themselves are not found in the fossil state, have wished to 
place in the T'emnopleuride, although they have neither true or false 
pits nor low sutural impressions, and their plates are not united 
by dowelling. These sea-urchins, attributed formerly to the genus 
Arbacina, Pomel, of which the type A. monzlis, Desm., has sutural 
impressions which are sometimes very difficult to observe, have lately 
been separated from it by Lambert et Thierry and been placed in the 
genus Prionechinus, Al. Agassiz. Unfortunately, this genus Przon- 
echinus has been wrongly defined and, moreover, imperfectly figured 
by its author, so that one is led to inquire if the fossil forms quite 
agree with the characters contemplated by Agassiz when he established 
this genus. Consequently I am of opinion that a new determination 
is necessary, and have proposed for this Echinid the name Pseudo- 
arbacina. 
I have also pointed out that among the Zemnechinus of the Gaj 
Series of India, the 7”. stellulatus, Duncan & Sladen, may be separated 
from this genus because it does not possess the false pits or low 
sutural depressions which characterize Zemnechinus, Forbes, Ope- 
chinus, Desor, and true Arbacina, Pomel. As 7. stellulatus presents 
a peculiar ornamentation, having its secondary tubercles united with 
the primary ones by radiating miliaries, it must be considered as the 
type of a new genus of the Triplechinine, for which I propose the 
name Brochopleurus. A form allied to B. stellulatus has been found 
by A. E. Pachundaki in the Miocene range of the Marmarica near 
Mersa Matru, and described in 1907 by Lambert under the name 
Opechinus fourtaut. 
The Temnopleuride are only represented in Egypt by a new form 
belonging to the genus Lepidopleurus, Duncan & Sladen. 
