HERAPATHITE 



560 



HERMAPHRODITE 



When dissolved, add an extremely minute drop of an 

 alcoholic solution of iodin. The first effect is the 

 production of the yellow, cinnamon-colored compound 

 of iodin and quinin, which forms as a small circular 

 spot ; the alcohol separates in little drops, which, by a 

 sort of repulsive movement, drive the fluid away ; 

 after a time the acid liquid again flows over the spot, 

 and the polarizing crystals of sulphate of iodoquinin 

 are slowly produced in beautiful rosets. This test suc- 

 ceeds best without the application of heat. 



Herapathite {her' ' -ap-ath-it) [from Herapalh, an Eng- 

 lish chemist]. An iodid of quinin-sulphate, occur- 

 ring in rhomboid laminae. It has been used as a 

 remedy in scrofula and in febrile cases ; in micros- 

 copy, it is employed in polarizing light. 



Herb {erb or herb) \Jierba, an herb]. An annual, bien- 

 nial or perennial plant, the stem of which contains 

 but little wood and dies down to the ground at the 

 end of the season. H. -doctor. See Herbalist. 

 H. -juice Cure. See Cure. 



Herbaceous {her-ba'-se-us) \_herba, grass]. In biology: 

 I. Applied to stems or other organs that have a 

 tender, juicy consistence and perish at the close of the 

 growing-season. 2. Feeding upon herbs. 



Herbal {her'-bal) \herba, grass]. An old name for a 

 book on herbs ; chiefly designating a book on the 

 medicinal virtues of herbs. 



Herbalist {her' '-bal-ist) \herba, grass]. An herb-doc- 

 tor or simpler ; a so-called botanic physician. 



Herbarium {her-ba' -re-um) \herba, grass]. A col- 

 lection of dried plants arranged for study ; a hortus 

 siccus. 



Herbicarnivorous {her-be-kar-niv' '-or-us) \herba, herb- 

 age ; caro, flesh ; vorare, to eat]. Omnivorous ; 

 living upon both animal and vegetable food. 



Herbivora {her-biv' -or-ah) \_hei-ba, grass ; vorare, to 

 devour]. A name given to a division of mammalia. 

 Animals that feed on vegetation. 



Herbivorous {her-biv' '-or-us) \_herba, grass ; vorare, 

 to devour]. A descriptive term applied to animals 

 that subsist on vegetation. 



Herbst's Corpuscles. A variety of sensory end-organs 

 found in the mucous membrane of the tongue of the 

 duck ; they resemble small Vater's corpuscles, but 

 their lamellae are thinner and closer to each other, while 

 the axis-cylinder within the central core is bordered 

 on each side by a row of nuclei. 



Hercogamy {her-kog' -am-e) [epnoq, a fence ; jd/uog, 

 marriage]. In biology, the prevention of impregna- 

 tion or fertilization by some structural obstacle ; 

 applied to flowers. 



Herculeus morbus {her-ku-le'-us mor'-bus) [L.]. 

 Synonym of Epilepsy. 



Hereditary {he-red' '-it-a- re) \heres, an heir] . Acquired 

 by inheritance. H. Disease, one transmitted from 

 parent to offspring. H. Parts. See Determinate. 

 H. Syphilis. See Syphilis. 



Heredity {he-red' -it-e) \hereditas, heredity]. The 

 principle or fact of the transmission of physical or 

 mental qualities or tendencies from ancestor to offspring. 

 Darwin's Theory of Heredity, or the Hypothesis 

 of Pangenesis, supposes that each of the different 

 cells of the body gives off gemmules {Plastidules of Els- 

 berg), ox germinal particles, that are capable of repro- 

 ducing their kind, and which are included in and consti- 

 tute the generative cells, and thus reproduce all of the 

 peculiarities of the original organism. Weissmann's 

 Theory of the Continuity or " Immortality ' ' of 

 Germ-plasma, is developed from Nussbaum's proposi- 

 tion that germ-substance is directly abstracted from the 

 developing ovum and preserved, without essential 

 alteration, to become, by giving rise to sexual elements, 



the germ-substance of another generation, by the 

 corollary that the whole nature of the animal or plant 

 depends upon its germinal substance, and that the 

 resemblance of the offspring to the parent is due to 

 every gonoblast containing some germinal matter. 

 According to Nussbaum and Weissmann the cells of 

 the embryo are separated into two kinds: (i) The 

 germ-cells, which become the sexual elements ; (2) 

 The somatic cells or body-cells, used as building-material 

 [Somatoplasm) of the individual. Kolliker and others 

 have demonstrated that no sharp distinction exists be- 

 tween germ-cells and somatic cells, so that speculations 

 based on such assumed difference necessarily fall to the 

 ground. Naegele's Theory of Idioplasm and Nutri- 

 tive Plasma, is a definite theory of germinal continu- 

 ity ; he assumes the formative force to reside in a specific 

 material substratum, i. e., idioplasm — essentially iden- 

 tical with Weissmann's germ-plasma. Minot as- 

 sumes idioplasm to be the nuclear substance, chro- 

 matin, the essential factor in the function of heredity, 

 and the nucleus, therefore, the organ of hereditary 

 transmission. De Vries' Theory of Intracellular 

 Pangenesis, suggests that the nuclear substance of 

 the germ-plasm is composed of minute particles, Pan- 

 genes, not cells, but the bearers of the properties of 

 the cells. There are also in the nucleus Nuclear 

 Rods, called also Idants, and Chromatin Rods, which 

 are built up of a series of ancestral plasms, called Ids, 

 each representing " an individuality." The doubling 

 and multiplication of these idants prior to fertilization 

 is in the interest of variety, or variation of form and 

 character of the subsequent individual. This theory 

 claims the same independence for all constituent parts 

 of the cell-body as Weissmann claimed for those of 

 the nucleus. The entire cell is called the Protoplast, 

 and its various living, independent parts are called 

 Pangenes. The cell is thus likened to a compound 

 organism or colony. 



Hering's Experiment. A delicate test of stereoscopic 

 vision in which the perception of degrees of depth is 

 tested by means of falling bodies, seen through a long 

 tube. H.'s Theory. See Color- sensation. 



Hermann's Difference-theory. See Difference. H.'s 

 Theory, a theory as to the causation of muscular con- 

 traction ; he claims that the formation of carbonic 

 anhydrid on contraction is not simply due to oxida- 

 tion, but rather to the decomposition of inogen, with 

 the formation of certain simpler products, of which 

 carbonic anhydrid is one, and sarcolactic acid and 

 myosin the others. 



Hermaphrodism, or Hermaphroditism {her-maf - 

 ro-dizm, her-maf '-ro-dit-izm) ['Ep^c, Mercury ; 

 'A(ppo6iT7j, Venus]. The co-existence in a single in- 

 dividual of completely developed ovaries and testicles, 

 or of at least one of each gland. H., Bilateral, an 

 ovary and a testicle on each side. H., Complex, a 

 rare instance of hermaphrodism in which there are pros- 

 ent both the internal and external organs of either sex. 

 H., Double. Same as H., Complex. H., Lateral, 

 an instance in which male organs (especially a testicle) 

 are more or less developed on one side, and female 

 organs (especially an ovary) on the opposite side. 

 H., Protandrous, applied to the phenomenon :i 

 hibited by most hermaphrodite platode worms, oi 

 developing the male sexual products before the female. 

 H., Spurious, doubtful, but not double, sex. H., 

 Transverse, an instance in which the external organs 

 indicate the one sex, and the internal the opposite. 

 H., Unilateral, on one side an ovary and a testicle, 

 on the other an ovary or a testicle. H., Vertical. 

 Same as //., Complex. 



Hermaphrodite {her-maf -ro-dit) ['Epfirfc, Mercury; 



