What is "caprella"

Screw \Screw\ (skr[udd]), n. [OE. scrue, OF. escroue, escroe, female screw, F. ['e]crou, L. scrobis a ditch, trench, in LL., the hole made by swine in rooting; cf. D. schroef a screw, G. schraube, Icel. skr[=u]fa.]

1. A cylinder, or a cylindrical perforation, having a continuous rib, called the thread, winding round it spirally at a constant inclination, so as to leave a continuous spiral groove between one turn and the next, -- used chiefly for producing, when revolved, motion or pressure in the direction of its axis, by the sliding of the threads of the cylinder in the grooves between the threads of the perforation adapted to it, the former being distinguished as the external, or male screw, or, more usually the screw; the latter as the internal, or female screw, or, more usually, the nut.

   Note: The screw, as a mechanical power, is a modification of the inclined plane, and may be regarded as a right-angled triangle wrapped round a cylinder, the hypotenuse of the marking the spiral thread of the screw, its base equaling the circumference of the cylinder, and its height the pitch of the thread.

2. Specifically, a kind of nail with a spiral thread and a head with a nick to receive the end of the screw-driver. Screws are much used to hold together pieces of wood or to fasten something; -- called also wood screws, and screw nails. See also Screw bolt, below.

3. Anything shaped or acting like a screw; esp., a form of wheel for propelling steam vessels. It is placed at the stern, and furnished with blades having helicoidal surfaces to act against the water in the manner of a screw. See Screw propeller, below.

4. A steam vesel propelled by a screw instead of wheels; a screw steamer; a propeller.

5. An extortioner; a sharp bargainer; a skinflint; a niggard.
   --Thackeray.

6. An instructor who examines with great or unnecessary severity; also, a searching or strict examination of a student by an instructor. [Cant, American Colleges]

7. A small packet of tobacco. [Slang]
   --Mayhew.

8. An unsound or worn-out horse, useful as a hack, and commonly of good appearance.
   --Ld. Lytton.

9. (Math.) A straight line in space with which a definite linear magnitude termed the pitch is associated (cf. 5th Pitch, 10 (b) ). It is used to express the displacement of a rigid body, which may always be made to consist of a rotation about an axis combined with a translation parallel to that axis.

10. (Zo["o]l.) An amphipod crustacean; as, the skeleton screw ( Caprella). See Sand screw, under Sand. Archimedes screw, Compound screw, Foot screw, etc. See under Archimedes, Compound, Foot, etc. A screw loose, something out of order, so that work is not done smoothly; as, there is a screw loose somewhere. --H. Martineau. Endless screw, or perpetual screw, a screw used to give motion to a toothed wheel by the action of its threads between the teeth of the wheel; -- called also a worm. Lag screw. See under Lag. Micrometer screw, a screw with fine threads, used for the measurement of very small spaces. Right and left screw, a screw having threads upon the opposite ends which wind in opposite directions. Screw alley. See Shaft alley, under Shaft. Screw bean. (Bot.)

    1. The curious spirally coiled pod of a leguminous tree ( Prosopis pubescens) growing from Texas to California. It is used for fodder, and ground into meal by the Indians.

    2. The tree itself. Its heavy hard wood is used for fuel, for fencing, and for railroad ties. Screw bolt, a bolt having a screw thread on its shank, in distinction from a key bolt. See 1st Bolt, 3. Screw box, a device, resembling a die, for cutting the thread on a wooden screw. Screw dock. See under Dock. Screw engine, a marine engine for driving a screw propeller. Screw gear. See Spiral gear, under Spiral. Screw jack. Same as Jackscrew. Screw key, a wrench for turning a screw or nut; a spanner wrench. Screw machine.

       1. One of a series of machines employed in the manufacture of wood screws.

       2. A machine tool resembling a lathe, having a number of cutting tools that can be caused to act on the work successively, for making screws and other turned pieces from metal rods. Screw pine (Bot.), any plant of the endogenous genus Pandanus, of which there are about fifty species, natives of tropical lands from Africa to Polynesia; -- named from the spiral arrangement of the pineapple-like leaves. Screw plate, a device for cutting threads on small screws, consisting of a thin steel plate having a series of perforations with internal screws forming dies. Screw press, a press in which pressure is exerted by means of a screw. Screw propeller, a screw or spiral bladed wheel, used in the propulsion of steam vessels; also, a steam vessel propelled by a screw. Screw shell (Zo["o]l.), a long, slender, spiral gastropod shell, especially of the genus Turritella and allied genera. See Turritella. Screw steamer, a steamship propelled by a screw. Screw thread, the spiral rib which forms a screw. Screw stone (Paleon.), the fossil stem of an encrinite. Screw tree (Bot.), any plant of the genus Helicteres, consisting of about thirty species of tropical shrubs, with simple leaves and spirally twisted, five-celled capsules; -- also called twisted-horn, and twisty. Screw valve, a stop valve which is opened or closed by a screw. Screw worm (Zo["o]l.), the larva of an American fly ( Compsomyia macellaria), allied to the blowflies, which sometimes deposits its eggs in the nostrils, or about wounds, in man and other animals, with fatal results. Screw wrench.

          1. A wrench for turning a screw.

          2. A wrench with an adjustable jaw that is moved by a screw.

             To put the screws on or To put the screw on, to use pressure upon, as for the purpose of extortion; to coerce.

             To put under the screw or To put under the screws, to subject to pressure; to force.

             Wood screw, a metal screw with a sharp thread of coarse pitch, adapted to holding fast in wood. See Illust. of Wood screw, under Wood.

Caprella \Caprella\ n. a genus somprising the skeleton shrimp.

Syn: genus Caprella.

Caprella is a large genus of skeleton shrimps belonging to the subfamily Caprellinae of the family Caprellidae. It includes approximately 170 species. The genus was first established by Jean-Baptiste Lamarck in his great work Système des animaux sans vertèbres (1801) to describe Cancer linearis (now Caprella linearis) and Squilla ventricosa (now Phtisica marina).

• Caprella acanthifera Leach, 1814
• Caprella acanthogaster Mayer, 1890
• Caprella acanthopoda Guiler, 1954
• Caprella advena Vassilenko, 1974
• Caprella aino Utinomi, 1943
• Caprella alaskana Mayer, 1903
• Caprella alaskensis Holmes, 1904
• Caprella algaceus Vassilenko, 1967
• Caprella andreae Mayer, 1890
• Caprella angulosa Mayer, 1903
• Caprella angusta Mayer, 1903
• Caprella arimotoi Takeuchi, 1993
• Caprella astericola Jankowski & Vassilenko, 1973
• Caprella bacillus Mayer, 1903
• Caprella bathyalis Vassilenko, 1972
• Caprella bathytatos Martin & Pettit, 1998
• Caprella bermudia Kundel, 1910
• Caprella bidentata Utinomi, 1947
• Caprella bispinosa Mayer, 1903
• Caprella borealis Mayer, 1903
• Caprella brachiata Arimoto, 1978
• Caprella branchella Arimoto, 1978
• Caprella brevirostris Mayer, 1903
• Caprella californica Stimpson, 1856
• Caprella carina Mayer, 1903
• Caprella carinata Arimoto, 1934
• Caprella caulerpensis Guerra-García et al., 2002
• Caprella cavediniae Krapp-Schickel & Vader, 1998
• Caprella centrota Vassilenko, 1972
• Caprella ceutae Guerra-García & Takeuchi, 2002
• Caprella chelimana Mayer, 1903
• Caprella ciliata Sars, 1883
• Caprella cilluroantennata Arimoto, 1934
• Caprella circur Mayer, 1903
• Caprella clavigera Vassilenko, 1972
• Caprella concinna Mateus & Mateus, 1991
• Caprella constantina Mayer, 1903
• Caprella corallina Arimoto, 1980
• Caprella corvina Mayer, 1903
• Caprella cristibrachium Mayer, 1903
• Caprella danilevskii Czerniavskii, 1868
• Caprella decipiens Mayer, 1890
• Caprella dilatata Krøyer, 1843
• Caprella dissona Arimoto, 1979
• Caprella drepanochir Mayer, 1890
• Caprella dubia Hansen, 1887
• Caprella edgari Guerra-García & Takeuchi, 2004
• Caprella equilibra Say, 1818
• Caprella equina Arimoto, 1978
• Caprella erethizon Mayer, 1901
• Caprella eurydactyla Vassilenko, 1974
• Caprella excelsa Vassilenko, 1974
• Caprella eximia Mayer, 1890
• Caprella extensimana Laubitz, 1995
• Caprella falsa Mayer, 1903
• Caprella ferrea Mayer, 1903
• Caprella fimbriata Vassilenko, 1994
• Caprella fretensis Stebbing, 1878
• Caprella generosa Arimoto, 1977
• Caprella gigantea Haller, 1880
• Caprella gigantochir Mayer, 1903
• Caprella glabra Aoki, 1991
• Caprella globiceps Dana, 1853
• Caprella gorgonia Laubitz & Lewbel, 1974
• Caprella gracilior Mayer, 1890
• Caprella gracilipes Grube, 1864
• Caprella gracillima Mayer, 1890
• Caprella grahami Wigley & Shave, 1966
• Caprella grandimana (Mayer, 1882)
• Caprella greenleyi McCain, 1969
• Caprella hirayamai Guerra-García & Takeuchi, 2003
• Caprella hirsuta Mayer, 1890
• Caprella imaii Utinomi, 1943
• Caprella incisa Mayer, 1903
• Caprella indeterminata Vassilenko, 1994
• Caprella inermis Grube, 1864
• Caprella iniqua Arimoto, 1980
• Caprella iniquilibra Mayer, 1903
• Caprella innocens Mayer, 1903
• Caprella insularis Laubitz, 1995
• Caprella irregularis Mayer, 1890
• Caprella japonica (Schurin, 1935)
• Caprella kincaidi Holmes, 1904
• Caprella kominatoensis Takeuchi, 1986
• Caprella kroyeri De Haan, 1849
• Caprella kuroshio Mori, 1999
• Caprella laevipes Mayer, 1903

• Caprella laeviuscula Mayer, 1903
• Caprella liliata Arimoto, 1979
• Caprella lilliput Krapp-Schickel & Ruffo, 1987
• Caprella linearis (Linnaeus, 1767)
• Caprella liparotensis Haller, 1879
• Caprella litoralis Vassilenko, 1972
• Caprella longicirrata Vassilenko, 1974
• Caprella longidentata Arimoto, 1934
• Caprella longimanus Stimpson, 1853
• Caprella luctator Stimpsom, 1855
• Caprella lukini Vassilenko, 1974
• Caprella madrasana Giles, 1890
• Caprella manneringi McCain, 1979
• Caprella mantis Latreille, 1816
• Caprella media Vassilenko, 1974
• Caprella mendax Mayer, 1903
• Caprella microtuberculata G.O. Sars, 1879
• Caprella minima Arimoto, 1980
• Caprella minuscula Arimoto, 1980
• Caprella mitis Mayer, 1890
• Caprella mixta Mayer, 1903
• Caprella modesta Herklots, 1861
• Caprella monai Guerra-García et al., 2001
• Caprella monoceros Mayer, 1890
• Caprella multituberculum Lee & Lee, 1996
• Caprella mutica Schurin, 1935
• Caprella nagaoi Arimoto, 1970
• Caprella natalensis Mayer, 1903
• Caprella nichtensis Brandt, 1851
• Caprella obtusifrons Utinomi, 1943
• Caprella okadai Arimoto, 1930
• Caprella oxyarthra Vassilenko, 1974
• Caprella pacifica Vassilenko, 1972
• Caprella palkii Giles, 1890
• Caprella paramitisGuerra-García et al., 2001
• Caprella parapaulina Vassilenko, 1974
• Caprella paulina Mayer, 1903
• Caprella penantis Leach, 1814
• Caprella pilidigitata Laubitz, 1970
• Caprella pilipalma Dougherty & Steinberg, 1953
• Caprella pinnigera Arimoto, 1980
• Caprella polyacantha Utinomi, 1947
• Caprella pseudorapax Guerra-García et al., 2001
• Caprella pustulata Laubitz, 1970
• Caprella rapax Mayer, 1890
• Caprella rhinoceros Mayer, 1903
• Caprella rhopalochir Mayer, 1903
• Caprella rinki Stephensen, 1916
• Caprella rotundidentata Vassilenko, 1972
• Caprella rudiscula Laubitz, 1970
• Caprella sabineae Guerra-García & García-Gómez, 2003
• Caprella sabulensis Guerra-García et al., 2001
• Caprella sanguinea Gould, 1841
• Caprella santosrosai Sanchez-Moyano et al., 1995
• Caprella sarsi Honeyman, 1889
• Caprella scabra Holmes, 1904
• Caprella scaura Templeton, 1836
• Caprella scitula Arimoto & Hirayama, 1979
• Caprella sedovi Gurjanova, 1933
• Caprella septentrionalis Krøyer, 1838
• Caprella simia Mayer, 1903
• Caprella simplex Mayer, 1890
• Caprella singularis Mayer, 1903
• Caprella soyo Arimoto, 1934
• Caprella stella Krapp-Schickel & Vader, 1998
• Caprella striata Mayer, 1903
• Caprella subinermis Mayer, 1890
• Caprella subtilis Mayer, 1903
• Caprella takeuchi Guerra-García et al., 2001
• Caprella tasmaniensis Guiler, 1954
• Caprella telarpax Mayer, 1890
• Caprella temperativa Arimoto, 1982
• Caprella tenella (Dana, 1853)
• Caprella tenuis Haswell, 1880
• Caprella traudlae Guerra-Garcia, 2004
• Caprella triodos Stebbing, 1910
• Caprella trispinisHoneyman, 1889
• Caprella tsugarensis Utinomi, 1947
• Caprella tuberculata Guérin, 1836
• Caprella ungulina Mayer, 1903
• Caprella unica Mayer, 1903
• Caprella uniforma La Follette, 1915
• Caprella vana Mayer, 1903
• Caprella venusta Utinomi, 1943
• Caprella verrucosa Boeck, 1871
• Caprella vidua Mayer, 1903
• Caprella vitjazi Vassilenko, 1992
• Caprella wirtzi Krapp-Schickel & Takeuchi, 2005
• Caprella zygodonta Vassilenko, 1974