The Neocortex of the Dog

This article describes the structural organization of the neocortex of the dog from purely morphological point of view. Series of 50 urn transverse sections were cut from the frozen right hemiencephala of adult greyhounds, stained by N issl's method, and drawn. His's method was then used to construct life-size lateral, dorsal and medial views of the hemiencephalon from 38 sections located at regular intervals. Once the cytoarchitectonic criteria to be used had been established on the basis of preliminary observations, all the sections of each hemiencephalon were examined microscopically and the cytoarchitectonic types observed in each mapped on the corresponding drawing. These maps were then projected onto lateral, dorsal and medial views of the whole hemiencephalon to produce a classical cytoarchitectonic map of the neocortex made up of 21 types, 7 of them agranular (with no inner granular layer), 2 dysgranular (with a granular layer with diffuse boundans) and the rest granular (with a well-defined layer IV). Various areas of cortex whose characteristics were intermediate between those of adjoinin areas were classified in a residual typus intermedius.     

The Neocortex of the Dog

This article presents abundant rigorous information concerning the whole of the neocortex of a gyrencephalate mammal (the dog), including the buried cortex. The outline of 50 μm transverse sections stained with cresyl echt violet were measured with a Vids II image analyser, measurements being taken between reference points which mostly consisted in the edges and bottoms of the sulci. These measurements were used to construct stripwise representations of the cortex of the sections, which were then joined to produce a flat map of the neocortex showing the locations of 21 structural types. The total extent of each type was calculated, together with proportion of the cortex which is hidden from view in classical cytoarchitectonic maps.     

Anatomy and Cholinergic Innervation of the Sinus paranalis in Dogs

Conventional methods have been used to study the general configuration of the wall of the Sinus paranalis in dogs. Apocrine tubular glands, elastic fibres and smooth-muscle fibres are the more significant elements of the wall, together with the epithelium and connective tissue. By means of the immunohistochemical method described in this paper, the results provide histochemical evidence for the presence of an AChE-positive reaction, and supposedly cholinergic nerve fibres in the wall of the dog anal sacs, mainly associated with subepithelial smooth muscle, vessels, and glands.