sulci

Plural of sulcus. sulci form (sul'si-fôrm), a. 1 2 Sulcate Stems. 1. Stem of Equisetum hiemale. 2. Stem of Ru bus villosus. [L. sulcus, a furrow, + form a, form.] Having the form or character of a sulcus; like a furrow or groove. IMG:content-2447.png:[blocks in formation] Brains of Rabbit (A), Pig (B), and Chimpanzee (C), showing some of the principal median sulci and gyri of the mammalian brain. Ol , hippocampal sulcus; Un , uncinate gyrus; M , marginal gyrus; C, olfactory lobe; Cc , corpus callosum; Ac , anterior commi ure; H , callosal gyrus; 19, internal perpendicular icular sulcus; Ca , calcarine sulcus; Coll , collateral sulcus; F , fornix; LT , lamina terminal is. (Compare other views of the same brains under gyrus .) tions of the surface of the brain: used with English or Latin context. See phrases under fi ure, and cuts under brain, cerebral, and gyrus. - Auriculoventricular sulcus, the transverse groove marking off the auricles from the ventricles of the heart. - Calcarine sulcus. See calcarine. - Callosal sulcus, the callosal fi ure, between the callosal gyre, or gyrus fornicatus, and the corpus callosum. - Callosomarginal sulcus. See callosomarginal and fi ure. - Carotid sulcus, the carotid groove on the sphenoid bone. See cut under sphenoid.- Central sulcus, the fi ure or sulcus of Rolando. See fi ure. - Collateral sulcus. See collateral. Crucial or cruciate sulcus (or fi ure), a remarkably constant sulcus of the cerebrum of carnivores and some other mammals, described by Cuvier in 1805, and first named (in French, as sill on crucial ) by Leuret in 1839. In the cat this sulcus begins on the median aspect of the hemisphere, reaches and indents the margin, and thence extends laterally for a distance equal to or greater than its mesal part. It has many variant forms of its name, as carnivoral crucial sulcus, sulcus cruciatus, fi ura crucia ta, sci ura cruciata, etc., and different names (as frontal fi ure, etc.) from varying views of its homology with any sulcus of the human brain. This question has been discu ed, but not conclusively settled. Two prevalent views are that the crucial sulcus is equivalent (1) to the callosomarginal sulcus of man, and (2) to the central or Rolandic sulcus of man. The question is of importance be cause some well-marked motor centers have been made out with reference to this sulcus in the lower animals.Fimbrial sulcus, the sulcus choroideus; the shallow furrow on the optic thalamus corresponding to the margin of the fimbria.-Frontal sulci, the sulci which separate the frontal gyri: the superior frontal sulcus marks off the middle from the superior gyrus, and the inferior frontal sulcus divides the middle gyrus from the inferior.- Gingivobuccal sulcus, the space between the gums and the cheek.-Gingivolingual sulcus, the space between the tongue and the gums. Hippocampal sulcus. See hip pocampal. Intraparietal sulcus, the sulcus dividing the superior from the inferior parietal lobule; the intraparietal fi ure. - Lateral, para central, parallel sulcus. See the adjectives. - Occipitotemporal sulcus, the collateral sulcus. - Orbital sulcus, one of several sulci of the frontal lobe of the brain, in relation with the orbit of the eye, and separating the orbital gyri (which see, under gyrus ). - Para median dorsal sulcus, the groove on the dorsal surface of the oblong at a and upper part of the spinal cord marking the division between the funiculus gracilis and the funiculus cuneatus. - Para pyramidal sulcus, a slight groove on the ventral surface of the oblong at a, running from the median fi ure upward and outward, bounding the pyramid laterally. - Parieto-occipital sulcus. See parieto - occipital fi ure, under parieto occipital. Peduncular sulcus, the great transverse fi ure of the cerebellum. - Post central sulcus, the shallow postrolandic sulcus separating the ascending parietal convolution from the superior parietal convolution. - Posterior sulcus of Reil. See posterior. Pre central sulcus. See pre central. - Splenial sulcus, the callosomarginal sulcus. Sulcus choroideus, a shallow groove on the upper surface of the optic thalamus, running from the anterior tubercle backward and outward.- Sulcus corporum quadrigeminorum longitudinal is, the median longitudinal furrow on the upper surface of the corpora quadrigemina. Sulcus corporum quadrigeminorum trans versus, the transverse furrow separating the nates from the testes of the brain.-Sulcus sulk crural is lateral is, small grooves just behind the post perforatus of the brain of the cat. Wilder and Gage, Anat. Tech., p. 489. - Sulcus intern us olive, the upward extension of the sulcus lateral is ventral is of the spinal cord, pa ing along the olivary body on the median side. Ober stein. Sulcus lateral is dorsal is, the groove on the spinal cord, extending up into the oblong at a, from which the dorsal roots of the spinal nerves emerge. Also called posterolateral groove. - Sulcus limitans, a name proposed by Wilder in 1881 for the usually obvious depre ion between the optic thalamus and the corpus striatum.Sulcus longitudinal is median us ventriculi quart i vel sinus rhomboidal is, the median furrow on the floor of the fourth ventricle of the brain. - Sulcus longitudinal is mesencephali, the furrow on the external surface of the mesencephalon, between the crusta below and the superficial lemniscus and brachia of the corpora quadrigemina above. - Sulcus occipital is anterior, a fi ure extending the occipitoparietal fi ure down over the convex surface of the cerebrum. The two fi ures are continuous in certain apes, but not normally in man. Also called sulcus occipital is extern us. - Sulcus oссіріtalis inferior, a longitudinal fi ure of the occipital lobe separating the second from the third occipital gyrus.Sulcus occipital is superior, a longitudinal fi ure of the occipital lobe separating the first from the second occipital gyrus. - Sulcus occipital is trans versus, a transverse fi ure seen on the upper and lateral surface of the occipital lobe, behind the parieto-occipital fi ure. -Sulcus óculomotorii, a groove on the median side of the crus cerebri, from which the third nerve i ues. It marks the boundary between the crusta and the tegmentum. Sulcus olfact or i us, the fi ure on the orbital surface of the brain bounding the gyrus rectus on the outer side. Along it lies the tractus olfact or i us. - Sulcus orbital is, the triradiate or H-shaped sulcus on the orbital surface of the frontal lobe. - Sulcus postolivaris, the post olivary sulcus, a short furrow on the side of the oblong at a just laterad of the olivary body. Sulcus spiral is, the spiral groove along the border of the lamina spiral is or spiral lamina, of the cochlea. - Sulcus triradiatus, a name proposed by Wilder in 1881 for the three-pointed depre ion which demarcates the corpora albicantia from each other and from the tuber cinereum.-Supercallosal sulcus, the callosomarginal sulcus. - Sylvian sulcus, the fi ure of Sylvius. See fi ure. - Temporal sulci, the fi ures on the outer surface of the temporal lobe. The superior is also called the parallel fi ure.-Triradiate sulcus. Same as sulcus orbital is. - Vertical sulcus, the pre central sulcus.