586 



isions that any reflex center .1. -rivet its 

 chief afferent impn : entering 



tin- cord. a.s a rule. alout two >-gment- higher; 

 that tin- lilH-r- of th iml column are 



arranged in a definite order frmn within outward, 

 the innermost represent ing tin- im-i di-tal part of 

 the tail: an- 1 that -limuhiti.-n of aiititi 



the dog jT.Kiu.-i-. cxten-ion. of the posterior tooli 



i of tin- limb ana resultant in.-\. m.-nt. 

 Tin- application of bile or ..f a >oluiinii .f biliary 

 M ]t> to tin* lirain <>f . .-rtaiii 



am-' ral-l.it. rat. ami guinea pig) 



. bral phenomena which varied with the 



ammaN. but were generally characterised by con- 

 Yulstou* and lorn of consciousness, accompanied by 



sali vat ion. 



:. po-ilion of the 



Mm. I. Dr. !:. \a\vrat-ki.of halldorf. 

 the fluid drawn from the sulwrachnoid space 

 It was limpid, of slightly saline la-te. 

 . alkaline. In-camc opalescent <."n boiling, and 

 ti, -.1 n.i fliH-ciili or eoagula ; luit undrr the 

 microscope isolated red and white corpuscles were 

 frequently vi-ible. The n-Milt of the author's 

 tents was, contrary to the results obtained by 

 HopjH- Seylcr ami* Hansom, the determination of 

 a substance present in health, which in all its prop- 

 erties agrees with grape sugar. The percentage 

 amount is smaller than that in blood, and varies in 

 different classes of the animal kingdom from one 

 tenth part to two tenth jiarts per cent. Pyrocat- 

 evhin is entirely absent. 

 SiMM'ial Senses. In a study of the perception 



of the direction and distance of sound. l>r. Albert 

 f (tlasgnw. con-idered how far the differ- 

 ence of phase with which a sound atTects the two 

 ears simultaneously may aid in judging n- direc- 

 tion in the light of his own experiments and of 

 the discoveries of 1'rof. Sylvanus I*. Thompson. 

 The author's experiments u|>on the tympanic mem- 

 brane showed that pressure of the chain of ossicles 

 of one ear inward caused the opposite ear to hear a 

 sound more loudly. This peculiar fact was shown 

 to be due. in all probability, to a reflex starting 

 from the labyrinth of the fir-t ear. and passing to 

 the tetiM/ir (ijin/Hini or Kta/M-tliii* or (more probably) 

 both th-se mu-cle- of the opposite ear m-ar which 

 the sound was produced. Thus the mu-cular sys- 

 -.f tin- two ears are in connection with one 

 another. As a positive phase of the sound wave 

 will relax the ItnKiir fi/m/Hini and render Oic > 



-n-c. and the negative phase will produce the 

 vident that by means of the 

 muscular sense we may be able to estimate the 

 phase of tt -ound wave in each ear. and by compar- 

 ing them In.th be able to localize roughly the 



n of a sound. 



The C..IM -lu-ions drawn by I)r. James Kerr Ix>ve 



from his vtu,lj,. of the transmission of deafness are 



that congenital deafness is horelitary in the direct 



the expression of a tendency which 



has been seen only in tin- collateral branches of a 



fami! Mitomical lesions on which demi 



depsndl ar- no4 on,., but many. The intermarriage 

 of the deaf, therefor.-, only perpetuates, without 

 accentual injr. the tendencN.' In (in-at I'.ritain the 



. v i- alN.nt the 



whet? hrith | ia rents were cungenitslly deal 



ititious or acquired deafness. :..hn^ in nnit- 



.. 'illy not hi-n-ilitary. 'I h<- lu-aring brnth- 



. nitally deaf-mute are as 



liable when they marry to ),a\. ."!, af progeny as the 

 deaf them- .'iiinity of the pare'ir 



phasi7^s famil\ r-hiMren t and many 



cases- tal deafness arise in t hi- ;i\. 



Describing in the K S ic-ty his investigation 

 of the sensitiveness of the retina to light and color. 



\V de W. Abn. | Bnl of tl.e extinction 



of HP ii of Qffhj in the retina. With an 



apparatu- \\hich he des.-rilied he found that the 

 smaller the -pot ,f illuiiiinaled surface t he 1. 

 duction in inten-ily of the li.u'ht is reijuircd. ami 

 that the amount 1 rediict in of the li^ht falling 

 on th' spot which produces just n seii-ation ,| 

 litfht i- connected \\ith the -i/.e of the spot l.\ .1 

 -imple formula, I = I i- the inten-it\ a'ml 



diameter of the spot. Kurt her. he found that 

 it i- the smallest diameter that <^<\<T\\^ llir i 

 sary reduction in IHI.MHI\. and nt the ai 

 the' illuminated sur: extineiion of li-ht 



at otl of the retina ..b-ys ihr sann 



Since a large and small area having 1 hr -aim- actual 

 illumination apprar to be ( .f dilTerenl bri^l,- 

 an investigation \\a- made .if the relative lumino-j- 

 ties of the two. and it was found that the\ 

 conn. -imjile law. The reduction of 



the intensity of a OolofeO ray to e\t in-ruish all i-olor 

 was iic\i mea-ureil with areas of dilTen-nt dimen- 

 sions, and it wa- shown that a.^ain the inten-ily of 

 the reduced lijjht was connected with tin- -i/e ..f 

 the -pot b\ a simple e\piv.sj,,|, similar to that of 

 .iiiiction ,,f all li^'lit : but the expmiential 00- 

 ellicient differed, indii-ating that li-ht ami color 

 are n.. i eoiineetcil in the nianiHT which might be 

 expected. The author found I hat all color fields 



an- of the -ailie form, the extent depellilillg solely 



upon the illumination and the area- of the , 

 imap- that falls on the retina: and that ihei 

 connection between the intensity of the color and 

 the extent of the Held which can be expressed by a 

 formula, as can also the connect ion bet ween 1 1 

 of the spot of illuminated surface and the extent, 

 of field. Curves of illumination were found for 



eijlial color fields, and curves of extent of field for 



every color in the pri-mat ic spect rum. Kxamining 

 into the relative sensitiveness to light of dill 

 points in the retina, the author found that there are 

 " iso-lunies." or fields of equal sensit ivene . which 

 appear to be of the same form as the color fields. 

 The author admitted that there are difficulties in 

 reconciling these results with cither the You 

 the Helmlioltx theory of color vi-ion. and -ug^ 

 a niolificat ion in the accepted theory of light and 

 color which may explain the connection bet 

 the two. 



A. rharpentier has undertaken to show that the 

 optic nerve may be the seat of vibrations a phe- 

 nomenon which should be distinguished from the 

 phenomena studied by Young, Shedford, and I'i<l- 

 well, in which a luminous sensation, once produced, 

 reappears once or twice after an interval of about. 

 one fifth of a second. This i< -imply a -a f re- 

 current images, while the retinal oscillations now 

 in question an- rhythmical and have an average 

 frequency ..f :{(> per second. These oscillations are 

 propagated both radially and in a circular direction 

 simultaneously. Kxperiim-nt- proving and illus- 

 trating the phenomena are cited in the an' 



Mi-eel laiieoii*. The be-t m.-thod of giving in- 

 struction in anat'-my wa- <liii dat the annual 

 meeting of the Briti-h Medical Association in .Mont- 

 real, when it was generally agreed that direction 

 is of the highe-t practical importance, and that 

 familiarity with topographical anatomy could hard- 

 ly be pushed too far: but that the advantages to be 

 derived from lecture- ami various aceenry means 

 of instruction ought not to be neglected. It was 

 pointed out that a well-thought-out scheme of lec- 

 tures should supply the learner with facts derived 

 from comparative anatomy and from histology 

 which should enable him to gain a clearer concep- 

 tion than can be obtained from text-books of the 

 structure, use, and fitness of the several parts and 



