Catalogue Jlaisonni. 465 



On the Organs of Voice in Birds, with numerous Plates. By 

 William Yarrell, Esq. F.L.S. — Ibid, p. 305. 



The object of this paper is the description of the muscles which are attach- 

 ed to the different parts of the windpipes of birds. 



" The muscles of the glottis, or superior larynx," says the author, " are 

 uniformly two pairs in all the birds I have examined ; but the muscles 

 of the interior or true larynx, all largely supplied with nerves, vary from 

 one pair to five pairs, according to the genus or species, affording a cor- 

 responding increase in the various qualities of the voice. 



Some few birds have no true muscles of voice at the inferior portion of 

 their tracheae. Cuvier describes the king of the vultures as being with* 

 out any ; and this is also the case with the condor and the spoonbill. 



The division of birds possessing one pair of muscles of voice, is by far the 

 most numerous, including the genera Falco and Strix ; some ot the In- 

 sessores, all the Rasores, Grallatores, and Natatores, with a few exceptions 

 only, which Mr. Yarrell indicates. These muscles, on account of their 

 place of insertion, have been named sterno-tracheal. 



Some of the birds possessing two pairs of true muscles of voicCj may be 

 considered as exceptions to a general rule, rather than otherwise, smce 

 they belong to those orders which usually possess but one pair." The 

 Indian crowned pigeon, the wood-grouse, and, among the Natatores, the 

 velvet duck, the golden eye, the red-breasted merganser, and the gan- 

 net, have a second pair of muscles of voice. 



Trachese possessing three pair of the muscles of voice, are confined entire, 

 ly as far as Mr. YarrelPs observations have extended, to the Psittacidas. 



Mr. Yarrell has not met with any bird possessing four pairs of true mus- 

 cles of voice. 



Those which possess five pairs are the Corvi, starling, thrush tribe, larks, 

 buntings, finches, warblers, swallows, &c. 



Considerations sur les Blocs, Sfc. Considerations on the trans- 

 ported Blocks of Primitive Rocks. By Engelspach Lariviere. 

 •Brussels, 1829. Pamphlet in 8vo. 



Over der Steenen, Sfc. On the Stones and Pebbles of the Heaths 

 of the Netherlands. By P. S. Schull. — Bydrarg, tot de NaturL 

 No. I. 1830. 



We have already had occasion to analyze several papers on the interest- 

 ing subject of the dispersion of boulders and transported blocks on the 

 plains of Germany, Holland, and the Netherlands ; and perhaps, after 

 the philosophical generalizations of Professor Brongniart, we felt most 

 pleasure in the novel views of Count Romanzof. 3Ir. Westendorp, in a 

 Dutch memoirj occupied himself with the same investigations in an histo- 

 rical point of view, and the geological bearing is the object of Mr. Engels- 

 pach's memoir. The blocks of Campine and of the Drenihe are quartz- 

 ites, dolomites, limestones, compact feldspar, granites, protogyne, sie- 

 nite, pegmatite, hornblende rock, diorite, hyalomicte, mica slate, gneiss, 

 and dolerite. The author considers as transported the white quartzites, 

 (sandstone, y of the duchy of Luxembourg, and describes the granite 

 boulders of Westphalia, Pomerania, Poland, JMecklenbourg, Branden- 

 bourg, &c. He accounts for the dispersion of these blocks by several 

 of some rocks less hard, the effect of volcanoes, and the impulse of 

 large masses of ice. The author believes, like most other geologists, 

 that these blocks came from Scandinavia. It will be remembered, how- 

 causes. The first is a projecting force ; the second the deterioration 

 ever, that Omallius d'Halloy has advocated an opinion much more in 

 harmony with the progress of the science. He supposes that commo- 

 tions or earthquakes have brought these granitic boulders, existing pre- 

 viously under the sand of the countries in which they are at present 

 found, to the surface of the soil. 



