SCIENTiriC SUMMARY. 
247 
7 th. The middle efferent ffhres are aU more or less directed forwards, as curvi- 
linear himdles, and are lost, after being divided into two principal parts (super- 
ffcial and deep), almost entirely in the regions of the opposite side to that 
whence thev originated. 
8th, The superior efferent fibres out of the cavity of the BJiomhoidal 
bodies as clearly made up bundles. 
9th. The superior olivary bodies wliich, in pouit of structure, are like the 
inferior ones, give off’ a series of secondary fibres, which disperse in all direc- 
tions. — Tide Bobins's Journal cU VAnatomie, &c.; and Medico-Chirurgical 
Review, No. LXVIII. 
Granular Layer of the Retina in the Whale. — Herr 0. Bitter thus describes 
the structure of this stratum in the nervous expansion of the whale’s eye. 
This layer consists of three kinds of fibres : (a) The fibres of the limitans ; 
(6) the branchings of the nerve-cells ; (c) the processes of the rods and bulbs. 
The fibres of the lunitans curve between the cells and form a beautiful net- 
work, the meshes of which become larger towards the ora serrata, but its 
framework is fine in the centre, though coarse near the ora serrata. In this 
net-work the processes of the rods, branching out in various directions, con- 
verge into greater branches, and finally form those of the cells properly so 
called. In the centre of the retina the j)rocesses of the rods run straight, com- 
bine rarely, and often end as wide as they began towards the cell ; as they 
approach the ora serrata the processes run more obliquely, combine to a 
gTeater extent, and the branches of the cells become proportionally broader. 
This explains very simply why the granula-layer in the centre of the retina 
is narrower, and consists of finer fibres. But the name of “granula-layer” is 
objectionable. Hence Herr Bitter proposes to term it the outer fibrous layer 
in contradistinction to the inner fibrous nervous layer. — Vide Henle & Pfeuffer's 
Zeitschrift fur Rat. Med., vol. XXI., part 3, 
Therapeutical Vcdue of Opium. — Some time ago a memoir appeared from 
the pen of M. Claude Bernard, ui the pages of the Comptes Rendus, upon 
the subject of the physiological action of the alkaloids of opium. In this the 
distinguished author set forth certain opinions. These have since been dis- 
cussed by a less known experimenter, M, Ozanam, who thus sums up the 
conclusions warranted by the results of his own investigations : — Therapeu- 
tically opium consists of three classes of constituents : {a) Calmative sub- 
stance, as morphine, opianine, and narceine ; (b) excitant substances, as 
narcotine and thebaine ; (c) mixed substances, which are alternately excitant 
and cahnative, as codeine. Examined from a point of view relating to “ anato- 
mical localization,” each element of opium may be said to have, besides a 
more or less marked general action, a sort of elective affinity for some special 
division of the nervous system : thus, morphine, opianine, and narcotme 
affect the hemispheres of the bram ; codeine operates upon the cerebellum 
and rachidian bulbs ; thebaine acts upon the superior or cervicodorsal region 
of the spmal chord, and narceine upon the lumbar portion. From these 
qualities opium constitutes a most valuable remedy, and whilst each of its 
remedies would, if taken separately, produce too exciting or depressing effects, 
when taken in the combined condition, they naturally correct each other — 
a fact whose importance has not yet been appreciated by practical physicians. 
— Vide Comptes Rendus, LIX., No. 10. 
