EAELY PALEOZOIC BRYOZOA OF THE BALTIC PROVINCES. 325 



but chiefly in which acanthopores are absent. Diaphragms are 

 closely arranged in the tapering proximal end, are few or wanting in 

 the rest of the immature region, and become crowded in the mature 

 zone. The earliest part of the zooecial tubes thus has the charac- 

 ters of mesopores. Hallopora, the type genus, is numerously repre- 

 sented both in individuals and species throughout the Ordovician, 

 Silurian, and earliest Devonian, 



Genus HALLOPORA, new name. 



Callopara Hall, Amer. Journ. Sci., ser. 2, vol. 11, 1851, p. 400; Nat. Hist. New 

 York, Pal., vol. 2, 1852, p. 144.— Nicholson, Pal. Province Ontario, 1874, 

 p. 61; Geol. Mag., new ser., vol. 1, 1874, p. 13. — Ulrich, Joxim. Cincinnati 

 Soc. Nat. Hist., vol. 5, 1882, pp. 154, 251. — Foerste, Bull. Sci. Lab. Denison 

 University, vol. 2, 1887, p. 172. — Hall and Simpson, Nat. Hist. New York, 

 Pal., vol. 6, 1887, p. xv.— Miller, North Amer. Geol. and Pal., 1889, p. 

 295._Ulrich, Geol. Surv. Illinois, vol. 8, 1890, pp. 372, 416; Geol. and 

 Nat. Hist. Surv. Minnesota, vol. 3, 1893, p. 275; Zittel's Textbook of Paleon- 

 tology (Eng. ed.), 1896, p. 275. — Simpson, Fourteenth Ann. Rep. State 

 Geologist New York for the year 1894, 1897, p. 588. — Nickles and Bassler, 

 Bull. 173, U. S. Geol. Surv., 1900, pp. 36, 186.— Bassler, Bull. 292, U. S. 

 Geol. Surv., 1906, p. 40. — Cumings, Thirty-second Ann. Rep. Dep. Geol. 

 Nat. Res. Indiana, 1907, p. 741. — Hennig, Archiv fur Zool., vol. 4, No. 10, 

 1908, p. 48. 



Monticulipora (section 1) Dybowski, Die Chaetetiden der Ostbaltischen Silur- 

 Form., 1877, p. 89. 



Not Callopora Gray, Norman, and Levinsen. 



Unfortunate as it may seem to the paleontologist, the well-known 

 generic name Callopora Hall must, according to the rules of nomen- 

 clature, be replaced by another term. Nickles and Bassler recog- 

 nized the facts, and in their Synopsis of American Fossil Bryozoa 

 published the following: 



In 1848 Gray (Proc. Zool. Soc. London, Appendix, 1848, and List of British Ani- 

 mals in the collection of the British Museum, 1848, pp. 109, 146) proposed the generic 

 term Callopora for a single species, the Flustra lineata of Linnseus, but the term failed 

 to gain acceptance, and the species lineata is now considered to be a Memhranipora. 

 As Callopora Hall has become deeply engrafted into literature, it seems undesirable 

 under the circumstances to replace it by a new name. 



However, Gray gave a description of his genus, poor as it may be 

 considered from the standpoint of to-day, and the important point 

 of his work is that he selected a type species. Callopora must, there- 

 fore, stand based upon this species, even though more recent work 

 should prove it to be a Memhranipora. Such excellent authorities 

 in the study of recent Bryozoa as Levinsen and Norman have worked 

 out the details of Gray's Callopora lineata and consider the genus a 

 vahd one. 



In view of the above, I propose the name Eallopora in honor of 

 the distinguished paleontologist James Hall, to replace his Paleozoic 

 genus Callopora. This new name seems most appropriate in com= 



