166 THE ECHINODERMS OF TORRES STRAIT. 
Key to the Species of Teniogyrus—Continued. 
Polian vessels 10; wheels 0.090 to 0.175 mm.; sigmoid bodies 0.185 to 0.230 mm. long, with greatest 
width only two-fifths as much and with inrolled end undivided; tentacle rods unknown; 
Hewaliantislands220ito}zouiathomsi ce eee ae eee. eee eee eet dubius! sp. nov. 
AA. Tentacles 10; polian vessel single. 
Sigmoid bodies in groups, at least dorsally, about 0.130 mm. long, forming papillze when body-wall is 
contracted; coast of southeastern Australia; littoral............. australianus (Stimpson), 1856 
Sigmoid bodies not in groups, but scattered in the body wall, more numerous ventrally; Japan, 55 to 
IZO0 fathoms tk RA Ae Sector Ns ee ee CAT Ss cidaridis (Ohshima), 1915 
Key to the Species of Trochodota.2 
A. Wheels with inner margin of rim uniformly serrated. 
B. Tentacle-rods simple, ends more or less forked or branched. 
C. Tentacles with 8 (4 pairs) or more digits. 
D. Inner margin of rim of wheels finely serrate (about 100 teeth); wheels 0.100 to 0.160 mm. 
across; sigmoid bodies 0.090 to 0.120 mm. long; tentacle-rods 0.050 to 0.060 mm.; New 
Lenland): Vises «Peis hee wee he a Tee ee dunedinensis (Parker), 1881 
DD. Inner margin of rim of wheels coarsely serrate or crenulate (about 35 to 55 teeth); wheels 
0.050 to 0.070 mm. across. 
Inner margin of wheel-rim with about 35 to 40 blunt, rounded teeth; Auckland Islands. 
benhami (Dendy), 1909 
Inner margin of wheel-rim with about 50 to 55 bluntly pointed teeth; Japan. 
japonica (yon Marenzeller), 1881 
CC. Tentacles with 4 or 6 (2 or 3 pairs) digits. 
D. Digits 6; wheels 0.037 to 0.105 mm.; sigmoid bodies 0.080 to 0.095 mm.; Japan...... rosea 
(Ohshima), 1914 
DD. Digits only 4. 
Inner margin of wheel-rim with about 50 teeth; wheels 0.060 to 0.080 mm.; sigmoid 
bodies 0.085 mm., with no hook at thickened distal end; Mediterranean Sea. . venusta 
(Semon), 1887 
Inner margin of wheel-rims with 60 to 80 teeth; wheels 0.035 to 0.100 mm.; sigmoid bodies 
0.120 to 0.180 mm., with a conspicuous hook at distal end; Victoria...... roebucki Joshua, 1914 
BB. Tentacle-rods long C-shaped, not branched at ends but with 6 to 10 projections on convex side; 
ERIE WA aemeeinG fice a Rete SE SCOUTS Goa SIGE RODS Tem onan a. diasema * sp. nov. 
AA. Wheels with inner margin of rim not uniformly serrated but teeth present in well-separated groups. 
B. Sigmoid bodies not in heaps or groups, but well scattered in body-wall; teeth of wheel-rim in six 
groups of about 7 each. 
Digits 6; wheels 0.154 to 0.182 mm. across; sigmoid bodies 0.125 to 0.150 mm.; tentacle-rods 
branched at ends only, 0.076 to 0.087 mm. long; Falkland Islands and southern South 
ATCT CH s,2 722 tala Sersd naevus i Oe Eee one purpurea (Lesson), 1830 
Digits 8 to 10; wheels 0.033 to 0.150 mm.; sigmoid bodies 0.120 to 0.130 mm.; tentacle-rods 
with projections on sides, 0.050 to 0.065 mm.; Victoria and South Australia . .allani (Joshua), 1912 
BB. Sigmoid bodies chiefly in little heaps or groups; few teeth on wheel-rim; 8 to 10 digits; sigmoid 
bodies 0.066 to 0.077 mm.; tentacle-rods branched at ends only, about 0.045 mm. 
longs) Murray Wslandsyess) scarce) ae oe eae re eee maculata sp. nov. (see above) 
Key to the Species of Toxodora. 
Size small, 30 mm. in length; color reddish brown; digits numerous, 10 to 16; off southeastern coast of 
INew "Hingland 255 os etc re ae ae EL oe See ferruginea Verrill, 1882 
Size large, 145 mm. in length; color purplish gray; digits few, about three pairs; Suruga Gulf, Japan. 
pacifica Ohshima, 1915 
ACHIRIDOTA. 
This genus still contains only the type-species from the Hawaiian Islands described 
as Anapta inermis by Fisher. The stout calcareous ring, each piece of which has a prom- 
inent anterior tooth, is an excellent character. 
' Described and figured by Fisher (1907, p. 735, pl. uxxxu, fig. 2) as “Teniogyrus, species.” It seems to me 
sufficiently different from contortus to warrant giving it a name. 
*Tt is almost impossible to make an accurate key to the species of this genus without reéxamination of several 
species. In his description of benhami Dendy fails to say whether the sigmoid bodies are scattered or in groups, and 
one does not know whether the number of teeth on the inner margin of the wheel, as shown in his figure, is exact or 
not. So in the descriptions of rosea, of the Japanese form which he identifies as dunedinensis but which I am here 
naming diasema, and of Scoliodota japonica Ohshima leaves out certain details which must be known before this key 
can be made reliable. None of these four species is accessible to me, but each seems to be valid. 
‘ diaonoc = distinct, in reference to the clear difference between it and dunedinensis, the New Zealand species to 
which Ohshima (1914, p. 478) referred the holotype of diasema. 
