GLOSSARY. 897 



Tbo'chal (Gr. troclios^ a wheel). Wheel-shaped ; applied to the ciliated di;jO 

 of the Rotifera. 



Tro-ohan'te'r (G-r. trmlio^ I run). A process of the upper part of the thigh- 

 bune {femur) to which are attached the muscles which rotate the limb. 

 There may be two, or even three, trochanters present. 



Teo'choid (Gr. trochos^ a wheel ; and eidos^ form). Conical, with a flat base : 

 applied to the shells of Forarrhiniftra and Univalve Molluscs. 



Tro'phi (Gr. trophos^ a nourisher). The parts of the mouth in insects which 

 are concerned in the acquisition and preparation of food. Often called 

 '* instrumenta cibaria." 



Teoph'o-some (Gr. trepko^ I nourish ; and sora*?, body). Applied collectively 

 to the assemblage of the nutritive zooids of any ilydrozo-.n. 



Tkun'oa-ted (Lat. trunco^ 1 shorten). Abruptly cut off; applied to univalve 

 shells, the apex of which breaks off, so that the shell becomes " decol- 

 lated." 



Tu-Eio'o-LA (Lat. tiiba. a tuoe ; and cola^ I inhabit). The order of Annelida 

 which construct a tubular case in which they protect themselves. 



Tu-Bic'o-Lous. Inhabiting a tube. 



Tu-bu-lar'i-da. 



Tu-ni-ca'ta (Lat. tunica^ a cloak). A class of Mollascolda which are envel- 

 oped in a tough, leathery case or " test." 



Tur-bel-la'ri-a (Lat. turho, I disturb). An order of Scol-cida. 



Titr'bi-na-ted (Lat. turbo^ atop). Top-shaped; conical, with a round base. 



Ul'na (Gr. olene^ the elbow). The outermost of the two bones of the fore- 

 arm, corresponding with the Jibitla of the hind-limb. 



Um'bel-late (Lat. uinhella^ a parasol). Forming an umbels, e., a number 

 of nearly equal radii^ ail proceeding from one point. 



Uit-BiL'i-OQS (Lat. for navel). The apertm'e seen at the base of the axis of 

 certain univalve shells, which are then said to be " perforated" or " um- 

 biUcated." 



Um'bo (Lat. for the boss of a shield). The beak of a bivalve shell. 



Um-brel'la. The contractile disc of one of the Lucernarida. 



Un"'ci-n'ate (Lat. uncus, a hook). Provided with hooks or bent spines. 



Un-guic'u-late (Lat. un-ffuis, nail). Furnished with claws. 



Un-gu-la'ta (Lat. ungula^ hoof). The order of Jl/ammafe comprising the 

 Hoofed Quadrupeds. 



Un'gu-late. Furnished with expanded nails constituting hoofs. 



U-isi-LOc'u-LAK (Lat. umis, one ; and loculus. a little purse). Possessing a 

 single cavity or chamber. Applied to the shells oi Foraminifera and Mol- 

 lusca. 



U'ni-valve (Lat. unus, one ; valvce, folding-doors). A shell composed of a 

 single piece or valve. 



U-bo-de'la (Gr. oura, tail; delos, visible). The order of the tailed Amphi- 

 bians (Newts, etc.). 



Ue'ti-oa-tin& Cells (Lat. urtica, a nettle). [See Cnidte.) 



Vac'u-oles (Lat. 'vacuus., empty). The little cavities formed in the interior 

 of many of the Protozoa by the presence of little particles of food, usually 

 surrounded by a little water. These are properly called " food-vacuoles," 

 and were supposed to be stomachs by Ehrenberg. Also the clear spaces 

 which are often seen in the tissues of many Coshnterata. 



Var'i-ces (Lat. varix., a dilated vein). The ridges or spinose lines which 

 mark the former position of the mouth in certain univalve shells. 



Vas'cu-lar (Lat. vas, a vessel). Connected with the circulatory system. 



Ve'lum (Lat. for a sail). The membrane which suri'ounds and partially closes 

 the mouth of the '' disc " of Medusce, or medusiform gonophores. 



Ven'tbal (Lat. venter^ the stomach). Kelating to the inferior surface of the 

 body. 



Ven'tri-ole (Lat. dim. of venter, stomach). Ap]''lied to one of the cavities of 

 the heart, which receives blood from the auricle. 



