LONGILINEO. — A term used to denote a human morphological type in which the developmental ratios of the body are shifted towards a predominance of longitudinal diameters over transverse ones and of the limbs over the trunk, giving the organism as a whole an appearance that is sometimes tall and well-developed, sometimes tall, slender, and drooping. The longilineal type is opposed to the brevilineal (q.v.).
The Italian constitutionalist school, particularly N. Pende, describes two varieties: the longilineal sthenic-tonic biotype and the longilineal hyposthenic-hypotonic biotype. In the former, there is a clear development in length of bodily forms, with the chest predominating over the abdomen, a well-proportioned and harmonious body; there is no excess of fat, muscles are rarely very developed but are toned; height, in both sexes, tends to exceed the norm. From the endocrine standpoint (q.V. ENDOCRINE, GLANDOLE, GLANDS), there is always present hyperfunction of the thyroid and pituitary, whether or not joined to that of the gonads and adrenals, whence a series of subvarieties. The conditions of functional equilibrium of the organism are good, sometimes excellent for the harmony and resistance of its systems. From the neuro-psychic standpoint, they are tachypragmatic and tachypychic, i.e., quick in movement and in psychic reactions; intelligence is good, of an intuitive, synthetic, and imaginative type, with a schizoid orientation. In particular, in the hyperthyroid and hyperadrenal variety, individuals are emotional and irritable; in the hypergenital and hyperpituitary (hyperhypophyseal) variety, they are more capable of control and reflection; in hyperthyroids, intelligence is excellent, in hyperpituitary individuals, memory is robust.
In the longilineal hyposthenic-hypotonic biotype, the disharmony develops a lengthening of the trunk and particularly of the limbs, giving the individual a slender, hypotonic, drooping appearance, with evident curves and humps (kyphosis and lordosis) of the spine, particularly in the cervico-dorsal and dorso-lumbar regions; the muscles are slender and hypotonic, fat is scarce; sexual characteristics are underdeveloped. From the endocrine standpoint, there is hyperthyroidism with hypogenitalism, hypoadrenalism, hypoparathyroidism with spasmophilia; the hypoadrenal variety is particularly predisposed to tuberculosis. From the psychic standpoint, they are not tachypragmatic or tachypychic; the mood is sentimentally depressed; intelligence is often very good, sometimes brilliant, but rapidly exhaustible, of a fantastic type, neither concrete nor practical.