XXX Journal of Compakativk Neuhology. 



fibres governing the erectile vessels in the comb and other analogous 

 appendages arise from the sympathetic system. The fibres supplying 

 the cervical appendages accompany branches of the anterior roots of 

 spinal nerves, while those passing to the head lie in the first and second 

 trigeminal branches. The lids and muscles of the feather papilhe are 

 also supplied by the sympathetic. 



The SviMPATHETic System. 



In the same line are the observations of Arloing.(i) After section 

 of the cervical sympathetic in the case of the o.k the corresponding part 

 of the snout became dry and soon began to desquamate. In the case of 

 the dog the eft'ect was not obvious for two months, but then followed 

 the same course. 



Recent researches of Doyon(2) showed that, while some vaso-dilator 

 fibres of the retinal vessels arise from the sympathetic, others lie in the 

 trigeminus. The author concludes from analogy that the vaso-con- 

 strictors are also in the trigeminus. The experiments consisted chiefly 

 in stimulation of the Gasser's ganglion after section of the sympathetic, 

 but without isolation of the ganglion. 



By a different method Langley and Dickinson, and later, Langen- 

 dorff", have endeavored to experimentally determine the function of the 

 cervical sympathetic.(^) 



Contribution to the Study of the Brain of Tracheate 

 Arthropod.s.(*) 



1. Technique. — Of several methods of preparation tried, the follow- 

 ing was found to yield the best results. After dissecting away the major 

 portion of the insect, the nervous system was hardened in osmic acid, 

 followed by alcohol. The brain was then stained /;/ toto with alum or 

 borax carmine. 



2. Histolo<ricol Elements. — The arthropod brain is composed of 

 three principal nervous elements: ganglionic cells, nerve fibres and 



1 S. Arloing, " Des rapports fonctionnels du cordon sympathetique cervical avec 

 I'epiderme et les glands," Arch, de Phys. normale et pathol., i8go, III, i, p. i6o. 



2 M. DovoN, " Recherches sur les nerfs vasomoteurs de la retine et en particulier sur 

 le nerf trijumeau," Arch, de Phys., 1890, III, i, p. 13. 



3 Langley and Dickinson, " On the Local Paralysis of Peripheral Ganglia, and the 

 Connection of Different Classes of Nerve Fibres with Them," Proc. Roy. Soc, XLVI, 

 p. 423 ; " The Connections of Peripheral Nerve Cells with the Nerve Fibres which Run 

 to the Sub-Lingual and Sub-Maxillary Glands," Journal of Physiology, XI. p. 123; "On 

 the Progressive Paralysis of the Nerve Cells of the Superior Cervical Ganglion," Proc. 

 Roy. Soc, XLVII, p. 379; " Pituri and Nicotin," Journal of PhyMology, XI, p. 265; 

 " Action of Various Poisons upon Nerve Fibres and Peripheral Nerve Cells," Journal of 

 Physiology, XI, Suppl., p. 509 O. Langexdokff. " Die Beziehungen der Nervenfasern 

 des Halssympathicus zu den Ganglienzellen des oberen Halsknotens," Centralblatt fiir 

 Physiologie, V, 5, June, 1891, p. 129-131. 



4 G. Saint-Remv, "Contribution a L'Etude du Cerveau chez les Arthropodes 

 Tracheates." Poitiers. 1890, 276 pp., 12 pi , 159 figs. 



