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water-weeds in ponds and puddles, or knotted together in an apparently inextricable coil. They may he several inches in length and are no thicker than a piece of See also:

WHIP

whip-See also:

CORD (derived through the Fr. corde, from the Lat. chorda, Gr. xop(5rt, the string of a musical instrument)

cord. The male is distinguishable from the See also:

FEMALE

female by the presence of a See also:

FORK (Lat. furca)

fork at the posterior end of the See also:

BODY

body. The body is covered by a cuticle which is sculptured and the various markings are of systematic importance: it is secreted by a hypodermis which also includes See also:

NERVE (Lat. nervus, Gr. vevpov, a bowstring)

nerve-cells and some gland-cells. In the adult aquatic See also:

STAGE (Fr. 6/age; from Lat. stare, to stand)

stage the alimentary See also:

canal shows signs of degeneration, and it seems probable that in this stage Gordian worms take no See also:

food. The mouth is terminal or subterminal; there is a weak sucking pharynx situated behind the See also:

BRAIN (A.S. braegen)

brain, and a See also:

long See also:

INTESTINE (Lat. intestinus, internal, usually in neuter plural intestina. from intus, within)

intestine lying along the medio-ventral body-cavity; it ends in a See also:

CLOACA

cloaca which receives the See also:

VASA, or NIKOLAISTAD

vasa deferentia in the male. There is a single unsegmented nerve-cord which runs along the ventral See also:

MIDDLE

middle See also:

LINE

line .and enlarges posteriorly into a caudal ganglion and anteriorly in a ganglion, the brain, which is not supra-oesophageal. The peripheral See also:

NERVOUS

nervous See also:

SYSTEM

system is minutely described by T, H. See also:

Montgomery. There is a median See also:

eye on the See also:

head. A,a,Female Heterodera schachtii See also:

Schmidt, breaking through the epidermis of a See also:

root; the head is still embedded in the parenchyma of the root.

B, a, larvae See also:

BORING

boring their way into a root; 6, larva of the immobile See also:

KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind surrounded by the old skin, living as an ectoparasite on the outside of the root. (From Strubell.) B, First motile larva. C, Second immovable parasitic larva casting its skin. D, A female with one See also:

HALF

half of the body-See also:

wall taken away to show the coiling generative See also:

ORGANS

organs. a, Boring apparatus. b, Oesophageal bulb. c, Excretory See also:

PORE

pore. d, Alimentary canal. e, Anus. f, Ovary. E, A male shortly before casting its larval skin. and only in the middle, region of the body are there any. body- cavities, the space within the body being usually filled up with parenchyma.

There are four closed spaces of the nature of body-cavities, two lateral and a dorso-median and a ventro- median. Into the former the ovaries project, though the lumen of the lateral body-cavity is quite shut off from the lumina of the ovaries or uteri. In the adult male the lateral body-cavities are absent. A curious duct with lateral branches termed the supra-intestinal See also:

ORGAN

organ lies above the intestine in the female. There are two See also:

SERIES (a Latin word from serere, to join)

series of ovaries extending through a large See also:

PART

part of the body and accompanied by two uteri; the latter open by two oviducts which debouch into an See also:

ATRIUM (either from ater, black, referring to the blackening of the walls from the smoke of the hearth, or from the Greek aiOpeov, open to the sky, or from an Etruscan town, Atria, where the style of building is supposed to have originated)

atrium which also receives the intestine and a single receptaculum seminis, and is continued back-See also:

ward as the cloaca; this opens posteriorly. The ovaries are See also:

EPITHELIAL, ENDOTHELIAL

epithelial sacs which open into the uteri. The paired testes extend through the greater part of the body and end in two vasa deferentia which unite with the intestine to See also:

FORM (Lat. forma)

form a cloaca. From See also:

Cambridge Natural The eggs are laid in the See also:

SPRING (from " to spring," " to leap or jump up," " burst out," O. Eng., springau, a common Teut. word, cf. Ger. springer, possibly allied to Gr. QnrFpxecOac, to move rapidly)

spring as a See also:

RULE

rule, See also:

HISTORY

History, vol. ii., "Worms," &c., by permission of Mac- and after about a See also:

WEEK (from A.S. wicu, Germanic *wikon, probably=change, turn)

week they give rise to a millan & Co., Ltd. F IG. 3.—Tarsal See also:

JOINT (through Fr. from Lat. junctum, jungere, to join)

joint See also:

minute, ringed larva with a protrusible of an Ephemerid larva boring apparatus corii,isting of three into which two Gordius chitinous rods. By the aid o; this the larvae, (a,a) have larva makes its way into the soft body penetrated. Magnified. of some See also:

INSECT

insect larva, Ephemerids, Chiro- nomids, or even of Molluscs, and encysts in the muscles or See also:

FAT (O.E. fdett; the word is common to Teutonic languages, cf. Dutch vet, Ger. Fett, &c., and may be ultimately related to Greek Irian, and =apos, and Sanskrit pivan)

fat body.

The insect, which may have become an imago with the Gordian larva still in it, is then eaten by a carnivorous insect or by a See also:

fish, and the contained Gordian larva becomes elongate and mature in its second See also:

HOST

host. After a See also:

YEAR

year or more this larva emerges into the water and commences to reproduce. The unexpected occurrence of these worms in pools and puddles, often in See also:

GREAT

great See also:

numbers, has given rise to myths about showers of worms. They occasionally make their way into the human See also:

STOMACH (Gr. vrbsaxos from arbga, a mouth)

stomach with the drinking-water and are vomited; but this is a See also:

case of pseudo-See also:

PARASITISM

parasitism—they are no true See also:

PARASITE (From Gr. irapa, beside, Tiros food)

parasite of See also:

man. There are a considerable number of See also:

SPECIES

species divided among the four genera: Gordius, Paragordius, Chordodes and Parachordodes; the last, a genus of Camerano's, is looked upon with some doubt by Montgomery. A See also:

FREE

free swimming marine form with See also:

LONGITUDINAL

longitudinal rows of bristles, known as Nectonema A. E. Verrill, may also come here, but at See also:

PRESENT

present its See also:

LIFE

life-history is unknown. The Nematomorpha form an isolated group; at first sight they seem to be connected with the See also:

NEMATODA

Nematoda, but in reality their only See also:

COMMON

common feature is the tubular genitalia opening into a cloaca, and it seems at present363 impossible to connect them with the See also:

ANNELIDA

Annelida. Until more is known it seems wisest to look upon them as an isolated assemblage of animals with no' near See also:

AFFINITIES

affinities to any of the great phyla.

End of Article: NEMATOMORPHA

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NEMERTINA, or NEMERTEANS (Nemerlea)