249 
ANATOMY OF THE HORSE. 
f 
which winds upward, gradually decreasing towards the apex, 
forming altogether about two turns and a half. If we make a 
vertical section of the cochlea, it presents the appearance of being 
divided into three cavities or separate compartments : this, how¬ 
ever, is not the case in its integral state, since the spiral turn¬ 
ings of the tube run from one into the other. 
Lamina Spiralis—Scala Cochlea. —There exists a structure in¬ 
side the cochlea, giving peculiar complexity to it, denominated 
the lamina spiralis. It consists in a partition or plate set edge¬ 
ways, partly osseous and partly membranous, running through 
the spiral tube of the cochlea, and dividing it into two separate 
gyrations, called the scalce cochlea , which at the apex run into 
each other and communicate. At the base, the external gy¬ 
ration communicates, through the fenestra rotunda, with the 
cavity of the tympanum; the internal gyration ends in the 
vestibule. 
Modiolus. —This is the central column or pillar around which 
the scalce perform their gyrations. It consists of a soft spongy 
structure, being pierced on every side like a colander, for the 
transmission of nervous filaments to lamina spiralis. 
Infundibulum. —Towards the apex of the cochlea the modiolus 
opens, the aperture bearing some resemblance to a funnel, being 
full and expanded upwards; this aperture is what is called the 
infundibulum. 
Meatus Auditorius Interims. —This is a small and entirely bony 
canal, piercing the petrous portion of the temporal bone, and 
running from the interior of the cavity of the cranium to abut 
against the vestibule and cochlea, for the conduct of the seventh 
pair of nerves. At its termination it is closed by a cribriform 
osseous plate, which is not flat, but bulges a little, through 
whose perforations are transmitted the fasciculi of the portio 
mollis. The principal part of this plate is set opposite to the 
cochlea; but a portion extends across to the vestibule : so that 
nervous filaments gain admission into both cavities. 
A FEW WORDS ON THE CAUSE OF SO GREAT A 
NUMBER OF CHRONIC AND INCURABLE LAME¬ 
NESSES IN HORSES. 
By Mr. Kerr, V. S., Southampton. 
A practitioner who has but seen a tolerable share of prac¬ 
tice, more especially the London veterinarian, cannot but be 
struck with regret, when he reflects on the very great number of 
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