Part 88

Mentum: a labial sclerite bearing the movable parts; attached to and sometimes fused with the sub-mentum; corresponds to the (united) stipes of maxillae: in Coleoptera, what is usually called mentum is really submentum: in Diptera, the term is applied to the posterior oral margin: in Hymenoptera, is part of "tongue," the second joint bearing the labial palpi, paraglossae and ligula.

Merdivorous: feeding upon dung or excrement: see scatophagous.

Meriaeum: the posterior inflected part of the metasternum in Coleoptera.

Meroistic: ovaries that secrete yolk or vitellaginous cells as well as ova.

Mesad: extending or directed toward the median plane.

Mesal: pertaining to, situated on or in the median plane of the body.

Mesenchym: that portion of the mesoderm that produces the connective tissues of the body.

Mesenteron: the mid-gut, stomach or chylific ventricle: the middle portion of the primitive intestinal canal, lined with entoderm.

Mesepimeron: in Odonata: the sclerite between humeral and first lateral suture.

Mesepisterna: in Odonata,- the oblique lateral pieces of mesothorax, meeting dorsally in a ridge.

Mesially: at or to the middle.

Mesinfraepisternum: a sclerite formed between propleuron, mesepisternum, mesepimeron and second coxa.

Meso: middle: as prefix, drops the o when stem begins with a vowel.

Mesoblast: the middles germ layer of the embryos: = mesoderm.

Mesoderm:= mesoblast: gives rise to muscular and circulatory systems.

Mesodont::= amphiodont: q.v.

Mesomeros: the 2d to 5th abdominal segments in Lepidoptera.

Meson: the middle plane of the body.

Mesonotum: the primitively upper surface of the 2d or middle thoracic ring.

Mesophragma: an internal prolongation of the metapraescutum, affording attachment to some of the wing muscles.

Mesopleura: in Diptera, the space before the root of the wing between the dorso- and sternopleural sutures: in Hymenoptera, the piece below the insertion of the wings.

Mesopleural bristles: in Diptera, are inserted in the angle formed by the dorso-pleural and meso-pleural sutures.

Mesopleural suture: in Diptera, runs from the root of the wings downward and separates the meso-pleura from the pteropleura.

Mesopleuron: the lateral surface of the meta-thorax.

Mesosternal cavity: in Elateridae, the opening into which the prosternal spine or mucro is fitted.

Mesosternal epimera: in Coleoptera; the narrow pieces separating the meta-sternal from the meta-sternal episterna.

Mesosternal episterna: Coleoptera; on each side of mesosternum between anterior border and epimera; generally separated by a distinct suture.

Mesosternal lobes: in Orthoptera; = mesosternellum, q.v.