PLATE II. 
Micromirra (PATERINA) BELLA (Billimgs) (p. 344). 
Ficure 1. Apical, posterior, and side views of a ventral valve. U.S. Nat. Mus. Cat. No. 51417a. Until the speci- 
men represented by fig. lc is found this valve may be regarded as typical of the species. (See pp. 335 
‘and 350 and fig. 6 of this plate.) 
la. Summit, posterior, and side views of a dorsal valve. U.S. Nat. Mus. Cat. No. 51417b. 
1b. Dorsal valve, showing a somewhat more elevated beak than in figure la. U.S. Nat. Mus. Cat. No. 51417c. 
The specimens represented by figures 1, la-b are all from Locality 49w, Lower Cambrian limestone one-fourth 
mile south of Emigsville, York County, Pennsylvania. 
Ficure le. Type specimen, from Locality 2n, Lower Cambrian limestone bowldersin conglomerate at Trois Pistoles, 
Quebec. Copied from Billings [1872b, fig. 18, p. 477]. The figure has been widely copied (see p. 
344), but the specimen from which it was drawn can not be located. (See pp. 335 and 350 and fig. 6 
of this plate.) 
Micromirra (PATERINA) LABRADORICA (Billings) (p. 347). 
Ficure 2. Enlarged drawing of the type specimen, from Locality 392a, Lower Cambrian at L’Anse au Loup, Straits 
of Belleisle, Labrador. Geol. Survey Canada. Specimen originally figured by Billings [1861h, fig. 6, 
p. 6]. 
2a. Dorsal valve. U.S. Nat. Mus. Cat. No. 18309a. Specimen figured by Walcott [189la, Pl. LXIX, fig. 
3b] as Kutorgina labradorica. 
2b. Posterior view of a small ventral valve. U.S. Nat. Mus. Cat. No. 18309b. 
2c. Partly exfoliated shell of a ventral valve. U.S. Nat. Mus. Cat. No. 18309c. Specimen figured by 
Walcott [1891a, Pl. LXTX, fig. 3a] as Kutorgina labradorica. 
2d. A more elevated ventral valve, which has been partly broken away along the cardinal margin. U.S. 
Nat. Mus. Cat. No. 18309d. Specimen figured by Walcott [1891a, Pl. LXIX, fig. 3] as Kutorgina 
labradorica. 
The specimens represented by figures 2a-d are from Locality 41a, Lower Cambrian limestone at Topsail Head, 
Conception Bay, Newfoundland. 
Frcure 2e. Dorsal valve from Locality 3a, Lower Cambrian shale on Hanford Brook, St. J ohn County, New Bruns- 
wick, Canada. U.S. Nat. Mus. Cat. No. 51428a. 
2f. Ventral valve associated with specimen represented by figure 2e. U.S. Nat. Mus. Cat. No. 51428b. 
Mrcromirra (PATERINA) LABRADORICA SWANTONENSIS (Walcott) (p. 348). 
Ficure 3. Apical view and side outline of a ventral valve, the type specimen. U.S. Nat. Mus. Cat. No. 15329a. 
3a. Apical view and side outline of a more elevated ventral valve. U.S. Nat. Mus. Cat. No. 15329b. 
3b. Dorsal valve associated in the same block of limestone with the specimen represented by figure 3a. 
U.S. Nat. Mus. Cat. No. 15329c. 
The specimens represented by figures 3, 3a—b were figured by Walcott [1886b, Pl. IX, figs. 2, 2a-b, respectively] 
as Kutorgina labradorica, and [1891a, Pl. LXIX, figs. 2, 2a-b, respectively] as Kutorgina labradorica swantonensis. 
Ficure 3c. Longitudinal section of a ventral valye showing the presence of a short pseudodeltidium. U.S. Nat. 
Mus. Cat. No. 15329d. 
The specimens represented by figures 3, 3a-c are all from Locality 25a, Lower Cambrian limestones, 2 miles east 
of Swanton, Franklin County, Vermont. 
Ficures 3d, 3e, and 3f. Apical, side, and posterior views of a specimen preserving the area and pseudodeltidium. 
This specimen can not be located. The drawing was labeled as having been made from a specimen 
in the collections of the American Museum of Natural History, but the officials inform me that they 
have no record of such a specimen. The locality is unknown. 
Mrcromirra (PATERINA) PROSPECTENSIS (Walcott) (p. 352). 
Ficure 4. Apical view of the type specimen, a ventral valve, from Locality 52, Lower Cambrian sandy shales, summit 
of Prospect Mountain, Eureka district, Nevada. 
4a. Dorsal valve associated with the ventral valve represented by figure 4. 
The specimens represented by figures 4 and 4a were figured by Walcott [1884b, Pl. TX, figs. la and 1, respectively; 
1886b, Pl. IX, figs. 3 and 3a, respectively; and 1891a, Pl. LXIX, figs. 4 and 4a, respectively] as Kutorgina prospectensis. 
U.S. Nat. Mus. Cat. Nos. 15335a and 15335b, respectively. 
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