214 



NATURE 



{June 28, 1883 



aromatic series from the even-atomic carbon. The specific 

 volume of carbon is C = 21 in the C n H„„ compounds of the 

 former ;eries, and C = 12 in the C n H 2n compounds of the second 

 series. — On Caucasus naphtha, by M. W. Markovnikoff and W. 

 Ogloblin, being a thorough analysis of it. — On the identity 

 (2ff,ir,")2a,'=(2a,A-,) c + 2ff,(7i(^'i-- r A) 2 > and its meaning: in physics, 

 by N. Slouguinoff. — On the focal properties of diffraction-nets, 

 by M. Merching. — On the specific properties of indiarubber, by 

 N. Hesehus. They cannot be explained by the presence of 

 air vehicles. 



To the Bulletin of the Belgian Academic Royale des Sciences, 

 for 1883, part 2, M. C. Malaise sends a valuable paper 

 on the constituent elements of the Silurian formations of 

 Brabant. An approximate thickness of 12,000 or 14,000 feet 

 is assigned to the various groups constituting the older 

 schistose rocks of this province. — Ed. Dupont deals with 

 the origin of the Belgian Carboniferous limestones ; and papers 

 are contributed by M. Terby on the aspect and positions of the 

 great comet of 18S2 ; by M. Chevron, on the inflammable 

 nature of the gases liberated in the decomposition of beetroot ; 

 by Baron Kervyn de Lettenhove, on the Conference of Bayonne 

 of 1565 ; by Alphonse Wauterson, on the origin and rise of the 

 early Heinish school of painting previous to the Van Eycks. — 

 Part 3 contains contributions by J, de Tilly, on Chasles' theorem 

 of central axes ; by Ed. Van Beneden, en some additions to the 

 : chth) olngical fauna of the Belgian seaboard ; by M. Genocchi, 

 on the algebraic functions of Frymand Hermite; by Joan Bohl, 

 on the reforms recently introduced into the commercial jurispru- 

 dence of Italy. 



Rendiconti of the Reale Isti'.ulo Lombardo di Scicnze e Letter,-, 

 April 12, 1883. — Some applications of symbolic variability to 

 mechanical problems, by S. C. C. Formenti. This paper is 

 concluded in the next number, April 26. — On springs, head 

 streams, and underground currents in the Italian Alps, by Prof. 

 T. Taramelli. — Experimental researches on the decomposition 

 of adipose substances in water, in damp earth, damp rooms, and 

 in water charged with 10 per cent, of ammonia, by C. A. 

 Tamassia. — A study of microscopic organisms in sweet, >alt, 

 and mineral waters, by Prof. L. Maggi. — Remarks on the 

 equivalence of magnetic and galvanic distributions, by Prof. E. 

 Beltrami. — A preliminary inquiry into Zanardelli's proposed 

 Italian penal code, by Prof. A. Buccellati. — On an unpub.ished 

 letter of Francesco Maurolico, dated September II, 1571, in 

 connection with the battle of Lepanto, by L. De-Marchi. — On 

 an example of realism in classic art, by Prof. J. Gentile. 



April 26. — A comparative study of the aracnofauna of Abys- 

 sinia and Shoa, by Prof. Pietro Pavesi. The author determines 

 thirty new species of spiders, for one of which ( Chins mofes) he 

 establishes a new order. — On the determination of the coefficients 

 of specific force for iron independently of Wohler's numbers, 

 by Prof. C. Clericetti. — Suggestions on a substitute for capital 

 punishment in Zanardelli's new Italian penal code, by Cesare 

 Oliva. — Remarks on banking and the cheque system introduced 

 into the new Italian commercial code, by L. Gallavresi. 



Atti of the Roman Reale Accademia del Lincei, April 1. — On 

 Finlay's comet (1882), by S. Respighi. — On the first observer of 

 the optical illusion converting convex into concave and concave 

 into convex surfaces, by S. Govi. The priority of discovery 

 usually assigned either to Joblot (171S) or to Christopher Cock 

 (1688) is here credited to Eustachio Divini (1663) on document- 

 ary evidence. — On the presence of native cinnabar and sulphide 

 of silver in the Tolfa Hills, by S. Blaserna. 



April 15. — Biographical notice of the late Uertrando Spaventa, 

 by S. Ferri. — On the migrations of the ancient peoples of the 

 Armenian Highlands and Asia Minor, studied in the light of the 

 Egyptian monuments and hieroglyphical inscriptions, by S. 

 Fiorelli. — A notice of the archaeological discoveries made in 

 various parts of Italy duriug the month of March, by S. Fiorelli, 



Revue Internationale des Sciences biologiques for March, 1883, 

 contains : — On the origin of the vertebrates and the principle of 

 the transformation of functions, by Dr. A. Dohrn. — On the exci- 

 tability of plants, by Dr. Burdon Sai derson. — On dwarfs and 

 giants, by D. L. Delbceuf. — Proceedings of the Academy of 

 Sciences, Paris, of the Belgian Academy, and of the Academy 

 of Amsterdam. 



April, 18S3, contains: — On the primordial flora, by Louis 

 Crie. — On the origin and relation of sex, by M. Debierre. — On 

 colour and mimicry in insects, by Dr. Hagen. — Proceedings 

 of the Academy of Sciences, Paris, and the Academy of Sciences, 

 Amsterdam. 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, May 10. — "Note on the Motor Roots of the 

 Brachial Plexus, and on the Dilator Nerve of the Iris." By 

 David Ferrier, M.D., LL.D., F.R.S., Professor of Forensic 

 Medicine in King's College. 



In a communication to the Royal Society (published in the 

 Proc. Roy. Soe., vol. xxxii. 1881) on the "Functional Relations 

 of the Motor Roots of the Brachial and Lumbo-Sacral Plex- 

 uses," my colleague Prof. Gerald Yeo and myself gave an 

 account of the results of electrical stimulation of the several 

 motor roots of the brachial and cvural plexuses in the monkey. 

 We there described the muscular actions of the upper extremity 

 as resulting from stimulation of the first dorsal up to the fourth 

 cervical nerve. 



The careful dissections made at our request by Mr. W. Tyrell 

 Brooks, Demonstrator in the Physiological Laboratory, King's 

 College, and a repetition of the stimulation experiments which I 

 have made, have revealed an error in the enumeration of the 

 roots of the brachial plexus which, in common with Prof. Yeo, 

 I w ish to correct. What we took for the fir-t dorsal nerve has 

 proved in reality to be the second dorsal. Hence the results of 

 the experiments must be read as applying to the spinal nerves 

 from the second dorsal to the fifth cervical respectively, instead 

 of from the first dorsal to the fourth cervical, as stated in our 

 paper. 



The anterior division of the second donal nerve in the monkey 

 apparently invariably gives a well developed communicating 

 branch to the first dorsal, besides giving off the second inter- 

 costal nerve and a branch to the stellate or inferior cervical 

 ganglion of the sympathetic. 



The three branches, as seen in a dissection made for me by 

 Mr. Brooks seem pretty equal in size, and all come off from the 

 main tiunk together. 



The brachial plexis in man is not usually, in text-books of 

 anatomy, comidered as deriving any of its component roots 

 below the first dorsal. In " Quain's Anatomy " (ninth edition, 

 p. 619), however, a brai.ch from the second to the first dorsal is 

 given as a variety. On this subject Dr. D. J. Cunningham has 

 published a note in the Journal of Anatomy and Physiology, 

 vol. xi. part iii., p. 539, 1877. Dr. Allen Thomson having 

 mentioned to him that he had on one or two occasions seen such 

 a communicating branch in man, he investigated the point, with 

 the result of finding a communicating branch from the second to 

 the first dorsal in twenty-seven out of thirty-reven dissections. 

 Of the ten cases where it was not found, five were so compli- 

 cated by previous interference in the dissecting-room or by 

 pleuritic adhesions and thickenings, that they may be considered 

 as doubtful. But, even including these, it appears that the 

 second dorsal sends a communicating branch to the first in 

 73 per cent, of the cases. Hence it should be considered as 

 more than a mere variety. If a perfect homology exists betwei n 

 the roots of the plexus in man and the monkey, the second 

 dorsal root would be the one presiding over the intrinsic muscles 

 of the hand. Presumably in those cases where it is not found, 

 its functions are represented in the fir>t dorsal. 



Dilator Nerve of the Iris. — Prof. Yeo and I mentioned in our 

 paper (sup. cit.) that in one case in which we directed special 

 attention to the pupil, stimulation of the anterior roots from the 

 first dorsal to the fourth cervical — in reality from the second 

 dorsal to the fifth cervical— caused no change in the pupil, 

 though the movements of the limb occurred with regularity. 



I have since inve-tigated this point during the course of 

 another research on which I have been for some time engaged. 

 I have experimented on four monkeys. The animals were 

 thoroughly narcotised with chloroform and kept so during the 

 whole course of the experiments. The posterior roots of the 

 nerves under investigation were cut, and the anterior stimulated 

 within the vertebral canal with a weak induced current from the 

 secondary coil (distant 20 to 15 cm.) of a Du Hois Keymond's 

 magneto-electromotor and one Daniell. As in former experi- 

 ments, a large flat electrode was placed on the sacrum as a 

 neutral point, the exciting electrode being a hooked needle, by 

 means of which the roots could be easily insulated and separately 

 stimulated. 



In the first experiment I failed to obtain dilatation of ihe 

 pupil from stimulation of the spinal roots from the second dorsal 

 up to the fourth cervical, though the functional activity of the 

 roots was indicated by movements of the limb. In the second 

 I exposed the dorsal roots from the eighth up to the third in- 



