101 
Dimensions. —Length, 4 • 2 mm. ; greatest height, 2 * 4 mm. 
Observations. —The thin chitinous-looking remains of this fossil make it 
referable to the Crustacea rather than to the mollusca. It does not fall into 
Hymenocaris on account of the minute size and only partially oblique contour ; 
whilst the posterior is not so produced and pointed as in that genus. From 
the ostracod Leperditia it differs in the apparently chitinous character of the 
carapace, otherwise it resembles some species of the genus like Leperditia 
canadensis, Jones. 
Its nearest analogue appears to be Lepeditta alata, Matthew. 1 
Explanation of Plates. 
Plate VI. 
Fig. Sphenothallus ftlicoides, sp. nov. Skeats coll, x 3. 
Fig. 2. Lingulella australis, sp. nov. 2a, profile. M.D. coll. 2 (7785). x 3. 
Fig. 3. Leptobolw truncata, sp. nov. Pedicle valve. 3a, profile. M.D. 
coll. (7836). x 3. 
Fig. 4. Acrothele subquadrata, sp. nov. Pedicle valve. 4a, profile. M.D. 
coll. (7812). x 3. 
Fig. 5. Acrothele brevis, sp. nov. Pedicle valve. 5a, profile. M.D. coll. 
(7929). x 3. 
Fig. 6. Billingsella tenera, Chapman sp. Pedicle valve. M.D. coll. 
(304). x 3. 
Fig. 7. Billingsella fergusoni , sp. nov. Holotype. Brachial valve. M.D. 
coll. (7838). x 3. 1 
Fig. 8. Billingsella fergusoni, sp. nov. Paratype. Pedicle valve. M.D. 
coll. (307). x 3. 
Fig. 9. Billingsella fergusoni, sp. nov. A cast. M.D. coll. (7799). x 3. 
Fig. 10. Eoorthis flexilis, sp. nov. Co-type. Natural cast of pedicle 
valve. M.D. coll. (7910). x 3. 
Fig. 11. Eoorthis flexilis, sp. nc . Jo-type. From a wax squeeze of a 
mould of the same valve. M.D. c . < /911). x 3. 
Fig. 12. Hebertella raristriata, \ lapman. Cast of a brachial valve. M.D. 
coll. (7786). x 3. 
Fig. 13. Eostrophomena skecUsi, sp. nov. Pedicle valve. Skeats coll, 
x 3. 
Fig. 14. Huenella divaricata, Chapman sp. Brachial valve. Plesiotype. 
M.D. coll. (7924). x 3. 
Fig. 15. Clitambonites Habelloides, Chapman sp. Pedicle valve. Squeeze 
from mould. M.D. coll. (7783). x 3. 
Fig. 16. Ditto. Pedicle valve. M.D. coll. (7909). x 3. 
Fig. 17. Ditto. Pedicle valve with few plicse. M.D. coil. (7893). x 3. 
Fig. 18. Grammysia heathcotiensis, sp. nov. M.D. coll. (7940). x 3. 
Plate VII. 
Fig. 19. Dinesus ida, Etheridge fil. A small cranidium, showing typical 
granulated surface. M.D. coll. (7859). x 3. 
Fig. 20. Ditto. A smooth (? decorticated) cranidium, showing neck ring 
and basal lobes. M.D. coll. (7849). x 3. 
Fig. 21. Ditto. A well preserved cranidium showing granulate surface, 
anterior and posterior lobes and furrowed glabella ; also frontal limb. M.D. 
co ll, (793 1). x 3. _ 
1 Trans. R. Soc., Canada, vol. III., 1886, p. 61, pi. VI,, figs. 16, 16a, 
* M.D. coll, signifies Mines Department collection. 
