GEOLOGY AND MINERALOGY. 53 



an undoubted description of a whale-fishery on the coast of the land 

 "Wisu. This, according to the admirable explanation of Frahn, is the 

 locality of the tribe Weg, spoken of in the Russian annals, north of 

 Novgorod, by the White Sea (Bielo Osero), thus identified with a bay 

 of the Arctic Ocean. D. W. 



SCIENTIFIC AND LITERARY NOTES. 



GEOLOGY AND MINERALOGY. 



" RIB-FOEMULiE IN BRACHIOPODS. 



In thet specific determination of fossil brachiopods, the palaeontologist has to 

 content himself in most instances with external characters. Amongst these may 

 be enumerated the ribs or plaits occurring so frequently on the shell. These 

 plaits, in adult forms, are either constant in their number, or vary only within 

 slight limits. Hence, when present, their number is commonly stated. V^e 

 suggest, for this purpose, the adoption of a numerical plan or formula, shewing 

 the number of ribs on each side of the sinus, and within it, or upon the mesial 

 fold, where this exists. Thus, when there, is a sinus, we may state, RF = 

 (pi\m\m), or (>?i||m); and when there is no sinus, RF = {m). In many forms, of 

 course, RF = ; and in the forms with an indefinite number of plaits, RF == 

 (00), or (001|00), or (00|m|00). As a general rule, the Spiriferidce, exclusive of 

 the smooth forms, show the rib-formula (ml|m) ; whilst the Rhynconellidce exhibit 

 (?n[m|m). The following are some examples : — 



Spirifer Niagarensis, Conrad (adult form), RF = (10-15||10-15) ; 8. sulcatus, 

 Hisinger, RF = (i-YJI^-T); 8. macropleura, Conrad, RF = (3-4||3-4) ; Rhynco- 

 nella {Hemithyris) nucula, Sowerby sp., RF= (6-8]3|6-8); R.formosa. Hall, RP 

 == (9-10|2-4|9-10). In the latter species, as in many others, the ribs within the 

 sinus are much coarser than those at the sides, a peculiarity which might be indi- 

 cated by larger or darker figures in the formula. 



As the plications on the mesial fold differ usually from those in the sinus, it fs 

 perhaps preferable, in these cases, to write the formula in two lines, one above 

 the other ; the numbei-s in the upper line referring to the valve which bears the 

 fold or elevation ; and those in the lower line, to that in which the sinus occurs. 

 Thus, in Atrypa (^Rhynconella) inerebescens, Hall, RF = (rtl§-i|i-|) ; or, more 

 simply (4-6|g|4 6), 



It is not of course to be supposed, that the method which we have here ven- 

 tured to suggest to the attention of palaeontologists, can be at all times very 

 rigorouslj applied ; but it is thought that, in many instances at least, it will be 

 found a convenient one. The student, for example, would find his labor much 

 facilitated, in the determination of an unknown species by reference to special 



