LITOPTERNA

litopterna, a suborder of south american tertiary ungulate mammals typified by _macrauchenia_, and taking their name ("smooth-heel") from the presence of a flat facet on the heel-bone, or calcaneum for the articulation of the fibula. the more typical members of the group were digitigrade animals, recalling in general build the llamas and horses; they have small brains, and a facet on the calcaneum for the fibula. the cheek-dentition approximates more or less to the perissodactyle type. both the terminal faces of the cervical vertebrae are flat, the femur carries a third trochanter, the bones of both the carpus and tarsus are arranged in linear series, and the number of toes, although commonly three, varies between one and five, the third or middle digit being invariably the largest. of the two families, the first is the _proterotheriidae_, which exhibits, in respect of the reduction of the digits, a curious parallelism to the equine line among the perissodactyla; in this feature, as well as in the reduction of the teeth, it is more specialized than the second family. the molar teeth approximate to the _palaeotherium_ type, but have a more or less strongly developed median longitudinal cleft. the three-toed type is represented by _diadiaphorus_, in which the dental formula is i.1⁄2, c.(0/1), p.(4/5), m.(3/8), and the feet are very like those of _hipparion_. the cervical vertebrae are of normal form, the orbit (as in the second family) is encircled by bone, the last molar has a third lobe, the single pair of upper incisors are somewhat elongated, and have a gap between and behind them, while the outer lower incisors are larger than the inner pair, the canines being small. the skull has a short muzzle, with elongated nasals. remains of this and the other representatives of the group are found in the patagonian miocene. in _proterotherium_, which includes smaller forms having the same, or nearly the same, dental formula, the molar teeth differ from those of _diadiaphorus_ by the deeper median longitudinal cleft, which completely divides the crown into an inner and an outer moiety, the two cones of the inner half being united. according to the description given by argentine palaeontologists, this genus is also three-toed, the single-toed representative of the family being _thoatherium_, in which the lateral metapodials, or splint-bones, are even more reduced than in the _equidae_. in the second family--_macraucheniidae_--the dentition is complete (forty-four) and without a gap, the crowns of nearly all the teeth being of nearly uniform height, while the upper molars are distinguished from those of the _proterotheriidae_ by a peculiar arrangement of their two inner cones, and the elevation of the antero-posterior portion of the cingulum so as to form an extra pit on the crown. to describe this arrangement in detail is impossible here, but it may be stated that the two inner cones are closely approximated, and separated by a narrow v-shaped notch on the inner side of the crown. the elongated cervical vertebrae are peculiar in that the arch is perforated by the artery in the same manner as in the llamas. in the santa cruz beds of patagonia the family is represented by the generalized genus _oxyodontotherium_ (in which _theosodon_ may apparently be included). it comprises animals ranging up to the size of a tapir, in which the nostrils were more or less in the normal anterior position, and the cheek-teeth short-crowned, with the inner cones of the upper molars well developed and separated by a notch, and the pits of moderate depth. the last upper premolar is simpler than the molars, and the canine, which may be double-rooted, is like the earlier premolars. the radius and ulna, like the tibia and fibula, are distinct, and the metapodials rudimentary. on the other hand, in _macrauchenia_, which was a much larger llama-like animal, the skull is elongated and narrow, with rudimentary nasals, and the aperture of the nose placed nearly on the line of the eyes and directed upwards, the muzzle not improbably terminating in a short trunk. deep pits on the forehead probably served for the attachment of special muscles connected with the latter. very curious is the structure of the cheek-teeth, which are high-crowned, with the two inner cones reduced to mere points, and the pits on the crown-surface large and funnel-shaped. in fact, the perissodactyle type is almost lost. the cervical vertebrae and limb-bones are very long, the radius and ulna being completely, and the tibia and fibula partially, united. the typical _m. patagonica_ is a pleistocene form as large as a camel, ranging from patagonia to brazil, but remains of smaller species have been found in the pliocene (?) of bolivia and argentina. the imperfectly known _scalabrinia_ of the argentine pliocene appears to occupy a position intermediate between _oxyodontotherium_ and _macrauchenia_, having the nasal aperture situated in the middle of the length of the skull, and the crowns of the cheek-teeth nearly as tall as in the latter, but the lower molars furnished with a projecting process in the hinder valley, similar to one occurring in those of the former. in this place may be mentioned another strange ungulate from the santa cruz beds of patagonia, namely, _astrapotherium_, sometimes regarded as typifying a suborder by itself. this huge ungulate had cheek-teeth singularly like those of a rhinoceros, and an enormous pair of tusk-like upper incisors, recalling the upper canines of _machaerodus_ on an enlarged scale. in the lower jaw are two large tusk-like canines between which are three pairs of curiously-formed spatulate incisors, and in both jaws there is a long diastema. the dental formula appears to be i.(1/3), c.(0/1), p.(2/1), m.(3/3). next _astrapotherium_ may be provisionally placed the genus _homalodontotherium_, of which the teeth have much lower crowns, and are of a less decidedly rhinocerotic type than in _astrapotherium_, and the whole dentition forms an even and unbroken series. the bodies of the cervical vertebrae are short, with flattened articular surfaces, the humerus has an enormous deltoid crest, suggestive of fossorial powers, and the femur is flattened, with a third trochanter. according to the argentine palaeontologists, the carpus is of the alternating type, and the terminal phalanges of the pentedactyle feet are bifid, and very like those of edentata. indeed, this type of foot shows many edentate resemblances. the astragalus is square and flattened, articulating directly with the navicular, although not with the cuboid, and having a slightly convex facet for the tibia. from the structure of the above-mentioned type of foot, which is stated to have been found in association with the skull, it has been suggested that _homalodontotherium_ should be placed in the _ancylopoda_ (q.v.), but, to say nothing of the different form of the cheek-teeth, all the other south american santa cruz ungulates are so distinct from those of other countries that this seems unlikely. it may be suggested that we have rather to deal with an instance of parallelism--a view supported by the parallelism to the _equidae_ presented by certain members of the _proterotheriidae_. (r. l.*) litotes (gr. [greek: litotes], plainness, [greek: litos], plain, simple, smooth), a rhetorical figure in which emphasis is secured for a statement by turning it into a denial of the contrary, e.g. "a citizen of no mean city," i.e. a citizen of a famous city, "a. is not a man to be neglected." litotes is sometimes used for what should be more strictly called "meiosis" (gr. [greek: meiosis], lessening, diminution, [greek: meion], lesser), where the expressions used apparently are weak or understated, but the effect is to intensify. litter (through o. fr. _litere_ or _litiere_, mod. _litiere_ from med. lat. _lectaria_, classical _lectica_, _lectus_, bed, couch), a word used of a portable couch, shut in by curtains and borne on poles by bearers, and of a bed of straw or other suitable substance for animals; hence applied to the number of young produced by an animal at one birth, and also to any disordered heap of waste material, rubbish, &c. in ancient greece, prior to the influence of asiatic luxury after the macedonian conquest, the litter ([greek: phoreion]) was only used by invalids or by women. the romans, when the _lectica_ was introduced, probably about the latter half of the 2nd century b.c. (gellius x. 3), used it only for travelling purposes. like the greek or asiatic litter, it had a roof of skin (_pellis_) and side curtains (_vela_, _plagae_). juvenal (iv. 20) speaks of transparent sides (_latis specularibus_). the slaves who bore the litter on their shoulders (_succollare_) were termed _lecticarii_, and it was a sign of luxury and wealth to employ six or even eight bearers. under the empire the litter began to be used in the streets of rome, and its use was restricted and granted as a privilege (suet. _claudius_). the travelling _lectica_ must be distinguished from the much earlier _lectica funebris_ or _feretrum_, the funeral bier on which the dead were carried to their burial-place.