to 
bent down; axis smooth in the centre, with transverse marking at the 
Sides; 14 joints; 8 pleurae. 
This is a doubtful species of Cryptonymus, but placed here on 
account of its characteristic tail. 
Crypronymus optusus, Ang., Pal. Scand., p. 3, plate 4, fig. 9. 
Cry ptonymus obtusus, Vogd., Mong. genera Zethus, p. 22. 
Nncrinurus obtusus, Pompecki, Tril., Fauna Westpreuss, p. 39, plate 5, 
figs, 25, 25-a. 
~—Wigand, Zeitschr. Deutsch. Geol. Ges. 1888, p. 92, plate 10, fig. 24. 
This species was described from a tail and part of the thorax from 
Reg. E, Gotland. 
The pygidium is triangular; axis with r2 joints, notched at the sides, 
With a row of central nodes; pleurae ro. 
Pompecki, plate 5, figs. 25 and 25-a, show 14 joints, with 1o pleurae. 
he anterior border of the hypostoma is very much produced in the 
Species (see Limdstrom Visual Org. T'ril., plate 4, fig. 15.) Plate 3, fig. 14. 
ENcrrnurus RARICOSTATUS, Walcott, Adv. sheets 31st Rep. N. Y. State 
Mus., p. 16, 1877; p. 69 of the report, 1879. 
Nncrinurus raricostatus, Safford & Vogdes, Proc. Acad. Nat. Soi, Phila, 1887, 
on n 167, fig. in text. 
in es us ERE TRORTE SHR, Yogne® Mon genera Zethus, 9 p. 
“Cerinurus raricostatus, Clarke, Geol. Minnesota, vol. 3, p. 740. 
Pygidium subtriangular, convex; length and breadth about equal. 
Axial not very prominent, with 16 joints. Pleurae 6. 
A similar species from the Trenton Limestone of Wisconsin was 
‘lescribed by Clarke, Geol. Minnesota, vol. 3, p. 739, as Zxcrin. vannulus, 
lhe author illustrated the head, thorax in part, and pygidium, The 
axis of the tail has 14 or 16 joints, with the first 6 or 7 joints extending 
Across it; the others are notched at the sides. Pleurae 6. 
CRvPronyatus LAKVIS, Angelin, Pal. Scand. p. 4, Plate IV, fig. 10, Reg” 
Ky. Gotland. 
~—Vogdes, Mong. genera Zethus, &c., p. 22, plate 2, fig. 10. 
~—Wigand, Zeitschr. Deutsch. Geol. Ges., 1888, p. 92, plate 10, fig. 25. 
The author figures an entire specimen. ‘The genal angles of the 
head are rounded, and the surface coarsely tuberculated. WT hOtas, 1 
*egments, Pygidium triangular, with 7 smooth pleurae; axial joints 14, 
Notched at the sides; centre smooth. 
ae The hypostoma has its anterior margin prolonged, which character- 
oe marks the species. (I,indstrom Visual Org. Tril., plate 4, fig. 16). 
See plate 3, fig. 16, 
J 
ais 
q & . . 
‘NCRINURUS BowNINGI, Foerste, Bull. Denison Univ., vol. 3, plate 22. 
ts = ee - 
B The author illustrates the elabella only, which he compares with 
4 Re . » 
: Barrandei, DeKon. 
