the echinoid fauna from japan and adjacent regions part i

212 S. NISIYA'VIA
76, pI. 1, figs. 1-3, 6-12, pI. 2, figs. 9-15, 19-21,pl. 45, figs. 27-28, text-figs. 53,55b (widely
distributed all over the Indo-Pacific regions, from East Africa to Japan, in depths about
0--45 metres).
Temnotrema POMEL, 1883, p. 87 (non A. AGASSIZ, 1863).-LAMI3ERT and JEANNET, 1935, p. 6.
Haplotype.-Temnopleurus hardwiekii (GRAY) A. AGASSIZ, 1872-74, pp. 166, 460, pI. 8a, figs.
1-3 (Japan) (in which A. AG.'\SSIZ included Te11l1lotrema seulptum, a quite distinct
species).
Test of moderate or small size, low, hemispherical or subconical, or flattened
above; generally slightly sunken at the peristomial edge. Pore-zones narrow, only
in the largest specimens slightly widening adorally; pore-pairs arranged more or less
distinctly in slightly oblique arcs of three. Trigeminate ambulacral plates of the
echinoid structure throughout; each plate with a primary tubercle of about the same
size as the interambulacral primaries. Secondary tubercles in larger specimens well
developed in the ambital region, almost as large as the primaries, forming horizontal
and longitudinal series. Horizontal sutures aborally with deep and usually large pits,
in ambulacra only one pit, ranging from the median suture to the base of the primary
tubercle; in interambulacra two pits, one from median suture, the other from outer,
adradial edge, the two being separated by the primary tubercle; pits sometimes
widened towards the primary tubercle; on the oral side the pits become smaller or
quite obsolete. Primary tubercles distinctly crenulate; the boss is sometimes distinctly
serrate especially below the ambitus. There may be more or less distinct depressions
on the plates, radiating from the primary tubercle. Apical system dicyclic, with
subcentral or pronouncedly eccentric position of the anal opening. Peristomial membrane
and buccal plates naked; in the adoral edge some small plates, outside the
buccal plates. Gill-slits very shallow; gills small, bush-shaped. Primary spines simple,
finely striated; marginal spines flattened towards the end, which is more or less
concave on the adoral side; peristomial spines usually curved, somewhat widened
and flattened at the point. Secondary spines simple, pointed. Globiferous pedicellariae
of one kind only, with or without lateral teeth. Spicules simple, bihamate, or sometimes
biacerate (from MORTENSEN, 1943).
The main point of distinction between this genus, to which Tem. alexandri (BELL,
1884) (Salmacis alexandri BELL, 1884-b, p. 118.-Sal. virgulata val'. DODERLElN, 1903,
p. 713, pI. 42, figs. 5-7a) is referred, and the allied genus Salmacis is that in Temnopleurus
there are large and deep sutural pits, while in the other there are only
angular pores.
Temnopleurus is a well known genus among the family of the Temnopleurids,
being characterized by the long and sharp angular pits, and by the well crenulated
primary tubecles, of which one to three or rarely more are found on a coronal plate
at the ambitus. Among the species which once placed in the genus Temnopleurlls
by LAMBERT and THIERY (1911, p. 218), Tem. neuvillei LAMBERT, 1912 (LAMBERT,
1912-a, p. 25, pI. 1, figs. 12-14-Eocene) and Tem. tuberclllosliS HAIME, 1853 (D'ARCHIAC
and HAIME, 1953-54 (53), p. 206, pI. 13, fig. 11.-DuNCAN and SLADEN, 1882-a, p. 85,
pI. 13, figs. 16-17) must be removed from this genus, and the former species is to be
referred to Medocechinus JEANNET, 1936 (jEANNET, 1936-a, p. 2), and the latter to
Trllmechinus LAMBERT and THIERY, 1911 (1911, p. 218). Among the fossil, the species
described by HERKLOTS from the Miocene of Java, Tem. areolatus HERKLOTS (1854,