228 



GLOSSARY. 



situated underneath the tongue, and limits the motions 

 of that member. 



FRONTAL (Lat. frons, frontis, the forehead). One 

 of the bones of the fore- 

 head in man, or one of 

 the corresponding bones 

 in one of the lower ani- 

 mals. See fig. 39. 



FUNCTIONAL. 

 Acting; performing a 

 function. 



FUNCTIONLESS. 

 Having no function; as 

 the splint-bones in the 

 leg of a horse. 



FUSED. Specifically 

 applied to bones united though originally distinct; that 

 is, either distinct in the embryo, in the young animal, or 

 in some allied form. 



GLAND (Lat. glans, glandis, an acorn). A part of 

 an organism yielding some special secretion. 



GLOTTIS (Gr.). The slit-like opening into the 

 trachea or windpipe. 



HALLUX (Lat. hallex, or allex, the thumb or great- 

 toe). The first digit of the hind-foot. See Digit. 



Fig. 24.— Skull of Black Indris. /Tem- 

 poral fossa ; 0. Orbit. In this case the 

 orbit is open behind and thus communicates 

 with the temporal fossa. 



Fig. 25. — Skull of Kangaroo. Observe the horizontal incisor of the lower jaw. 

 i. Incisors, z.a. Zygomatic arch. 



Fig. 26.— a. Upper, b. Lower Jaw of the Colugo or Flying-cat {Galeopithccus 

 volaiis) ; c. Front portion of the lower jaw, showing the pectinate incisors ; 

 d. Section of one of the pectinate incisors (magnified). 



HEEL (of a tooth). A portion of the tooth extending 

 horizontally from the base. 



HOLOTHURIAN. A member of the sea-cucumber 

 order of echinoderms, or the class which includes the 

 sea-urchins. 



HOMOLOGOUS (Gr. homos, same, and logos, ratio 

 or proportion). Corresponding in structure though not 



in function, as the arm of a man and the wing of a 

 bat. 



HONEY-COMB BAG. Same as Reticulum. 



HOOFS. Horny coverings encasing the toes all round. 

 — Accessory hoofs, the small hoofs present in sheep, goats, 

 and other members of the cow family at some distance 

 above the ground, representing the absent second and 

 fifth digits. See Digit. 



HUMERUS (Lat.). The bone of the upper arm or 

 corresponding bone in the lower animals. 



HYOID (Gr. X, and eidos, form). The Y-shaped 

 bone at the root of the tongue, which it. serves to support 

 in vertebrates. 



INCISOR (Lat. incido, to cut into). One of the teeth 

 situated in the premaxillse (in the front of the mouth) in 

 the upper jaw, or the corresponding teeth in the lower 

 jaw; so called because generally adapted for cutting or 

 dividing. Their form is exceptional in rodents, hippo- 

 potamuses, many marsupials, the flying cat (Galeopi- 

 thecus), and some other animals. See figs. 2, 6, 9, 25, 

 26, and 36. 



INDECIDUATE (Lat. in, not, and decide, to fall off). 

 Applied to a placenta which is not wholly extruded from 

 the body of the parent at the time of the birth of the 

 young animal. See Deciduate. 



INDEX (Lat., a pointer). The fore-finger, or second 

 digit of the extremity of the fore-foot. 



INGUINAL (Lat. inguen, the groin). Pertaining to 

 or situated in the region of the groin. 



INSECTIVORA (Lat. insedum, an insect, and voro, 

 to devour). An order of mammals mostly adapted for 

 feeding on insects. See fig. 35. 



INSECTIVORE. A member of the Insectivora. 



INSECTIVOROUS. Pertaining to the Insectivora; 

 insect-eating. — Insectivorous dentition, a dentition of a 

 simple kind, in which the teeth are exceptionally uniform 

 in character, generally more or less conical in shape. 



INTERDIGITAL (Lat inter, between, and digitus, 

 a finger). Situated between the fingers or digits. — 

 Inter-digital glands, glands situated on the hoof-bearing 

 joints of many ruminants. See body of the book, vol.-ii. 



P- 73- 



INTERMAXILLARY (Lat. inter, between, and 



maxilla, the bone at the side of the upper jaw). Same 



as premaxilla; so called because the two premaxillse are 



contiguous and lie in the middle of the mouth between 



the two- maxillae. 



ISCHIAL CALLOSITIES. Naked warty patches 

 on the hips of many monkeys. 



ISCHIUM (Lat.). The lowermost or hindmost part 

 of the hip-bone, a separate bone in the embryo. 



JUGAL BONE. The cheek-bone; the bone external 

 to the eye and giving prominence to the cheek. In a 

 group of the sloths this bone is characterized by a well- 

 marked descending process. See fig. 19. 



KA1NOZOIC (Gr. kainos, new, and zoe, life). In 

 geology, same as Tertiary. See Geological Table, 

 vol. i. p. 23. 



LACHRYMAL (Lat. lachryma, a tear). Pertaining 

 to tears, or to the place where tears are formed. — Lachry- 

 mal bone, one of the bones which compose the lower 

 part of the orbit. — Lachrymal sinus, a depression in the 



