624 CAMBRIAN BRACHIOPODA. 



(6.4 km.) south of Little Bras d'Or Lake; (31i) shale and shaly limestone on McNeil Brook, 1.5 miles (2.4 km.) east 

 of Marion Bridge; and (372e [Matthew, 1903, p. 50]) shales on McMullins Brook, near McLeod Brook (=Barachois 

 River); all in eastern Cape Breton, Nova Scotia, Canada. 



(308 [Matthew, 1901a, p. 278]) Shales of Division C3c of Matthew at Navy Island, St. John Harbor, St. John Comity, 

 New Brunswick, Canada. 



Specimens somewhat doubtfully referred to this species occiir at the following locality: 



TTpper Cambrian : (10c) Shales in a horizon 50 feet below that of Locality 10k, on the west side of Barachois 

 River, eastern Cape Breton, Nova Scotia, Canada. 



SCHIZAMBOK TYPICALIS Walcott. 



Plate LXXXIV, figures 1, la-d. 



ScMzambon typicalis Walcott, 1884, Mon. U. S. Geol. Survey, vol. 8, pp. 70-71, PI. I, figs. 3, 3a-d. (Described and 



discussed as a new species. Figs. 3, 3a-d are copied in this monograph, PI. LXXXIV, figs, la, 1, Ic, lb, and 



Id, respectively.) 

 fSchizambon typicalis Walcott, Hall and Clakke, 1892, Eleventh Ann. Rept. State Geologist New York for 1891, p. 



253, PI. IV, figs. 18-20. (Mentioned imder genus ScMzambon. Fig. 18 is copied from Walcott, 1884b, PL I, 



fig. 3a.) 

 ScMzambon typicalis Walcott, Hall and Clarke, 1892, Nat. Hist. New York, Paleontology, vol. 8, pt. 1, pp. 114, 116, 



and 117; fig. 65, p. 114; and PI. IV, figs. 27-30. (Mentioned in discussion of genus ScMzambon. Fig. 65 is 



copied from Walcott, 1884b, PL I, fig. 3a. Figs. 27 and 29 are copied from figs. 19 and 20, respectively, of the 



preceding reference.) 



This species is fully described in Monograph VIII of the United States Geological Survey 

 [Walcott, 1884b, pp. 70-71]. There is little to add to the description. For comparison with 

 the other species the original figures are reproduced. 



Among the fossils occurring in limestone bowlders from Locality 30w there is a single 

 specimen of a rentral valve of a shell that appears to be identical with ScMzamhon typicalis. 

 The points of identity are: (a) general form; (b) shape of foraminal opening; (c) fine, ele- 

 vated, concentric strise. The only difference is the greater convexity, which is owing, I think, 

 to the character of the matrix, the Nevada specimen being in a shaly limestone and somewhat 

 compressed. 



Formation and locality. — lower Ordoviclan: (201a) Pogonip limsstone, east slope of the ridge east of Hamburg 

 Ridge, Eureka district [Hague, 1892, Atlas], Eureka County, Nevada. 



TTpper Cambrian: (30w) Drift bowlder of limestone supposed to have come from la of the Notch Peak limestone 

 on Notch Peak [Walcott, 1908f, p. 175], found about 2 miles (3.2 km.) south of Marjum Pass, House Range [Walcott, 

 1908f, PL XIII], Millard County; (33d) ^^ thin-bedded blue limestone at the base of the first high point southwest of 

 the J. J. Thomas ranch, on the east side of the Fish Spring Range, Juab County; and (54c) about 1,100 feet (335.3 m.) 

 above the Middle Cambrian and 120 feet (36.6 m.) below the top of the Upper Cambrian in the central portion of the 

 limestone forming 1 of the St. Charles formation [Walcott, 1908f, p. 192], in Blacksmith Fork Canyon, about 10 miles 

 (16.1 km.) east of Hyrum, Cache County; all in Utah. 



Genus SIPHONOTRETA de Verneiul.b 



{tri^iwv, a siphon or tube; t/jjitoj- , perforated.] 



Crania Eichwald (in part) [not Retzius], 1829, Zoologia specialis, vol. 1, p. 273. (Described in Latin. The genus 



includes species other than those belonging with Siphonotreta.) 

 Terebratula Eichwald (in part) [not Lhwyd], 1840, Jour. Natur- und Heilkunde Medizinischen Akad. St. Petersburg, 



pts. 1 and 2, p. 138 (p. 24 in second part of one edition). (Merely places " Crania unguiculata and C. verrucosa" 



in this genus.) 

 , Terebratula Eichwald, 1842, Die Urwelt Russlands, Hft. 2, p. 145. (Merely mentions " Terebratula unguiculata.") 

 Siphonotreta db Verneuil, 1845, G6ologie de la Russie d'Europe, by Mujchison, de Verneuil, and de Keyserling, 



vol. 2, pt. 3, p. 286. (Described in French as a new genus.) 

 Siphonotreta de Verneuil, Kutorga (in part), 1848, Verhandl. Russ.-kais. min. Gesell. St. Petersburg for 1847, No.- 



12, pp. 261-263. (Described and discussed in German. Notes on the genus occur at various places on pp. 



250-260.) 

 Siphonotreta de Verneuil, Morris, 1849, Annals and Mag. Nat. Hist., 2d ser., vol. 4, pp. 315-320. (Notes on the genus 

 I and its generic relations.) 



a This species is somewhat doubtfully identified from this locality. 



b The synonymy for this genus is not complete; it includes only those references dealing with the species taken up in this monograph. 



